WorldWideScience

Sample records for cartilage-retaining wafer resection

  1. Adhesive wafer bonding

    Science.gov (United States)

    Niklaus, F.; Stemme, G.; Lu, J.-Q.; Gutmann, R. J.

    2006-02-01

    Wafer bonding with intermediate polymer adhesives is an important fabrication technique for advanced microelectronic and microelectromechanical systems, such as three-dimensional integrated circuits, advanced packaging, and microfluidics. In adhesive wafer bonding, the polymer adhesive bears the forces involved to hold the surfaces together. The main advantages of adhesive wafer bonding include the insensitivity to surface topography, the low bonding temperatures, the compatibility with standard integrated circuit wafer processing, and the ability to join different types of wafers. Compared to alternative wafer bonding techniques, adhesive wafer bonding is simple, robust, and low cost. This article reviews the state-of-the-art polymer adhesive wafer bonding technologies, materials, and applications.

  2. Candida parapsilosis meningitis associated with Gliadel (BCNU) wafer implants.

    LENUS (Irish Health Repository)

    O'brien, Deirdre

    2010-12-15

    A 58-year old male presented with meningitis associated with subgaleal and subdural collections 6 weeks following a temporal craniotomy for resection of recurrent glioblastoma multiforme and Gliadel wafer implantation. Candida parapsilosis was cultured from cerebrospinal fluid (CSF) and Gliadel wafers removed during surgical debridement. He was successfully treated with liposomal amphotericin B. To our knowledge, this is the first reported case of Candida parapsilosis meningitis secondary to Gliadel wafer placement.

  3. Candida parapsilosis meningitis associated with Gliadel (BCNU) wafer implants.

    LENUS (Irish Health Repository)

    O'Brien, Deirdre

    2012-02-01

    A 58-year old male presented with meningitis associated with subgaleal and subdural collections 6 weeks following a temporal craniotomy for resection of recurrent glioblastoma multiforme and Gliadel wafer implantation. Candida parapsilosis was cultured from cerebrospinal fluid (CSF) and Gliadel wafers removed during surgical debridement. He was successfully treated with liposomal amphotericin B. To our knowledge, this is the first reported case of Candida parapsilosis meningitis secondary to Gliadel wafer placement.

  4. Electrical Interconnections Through CMOS Wafers

    DEFF Research Database (Denmark)

    Rasmussen, Frank Engel

    2003-01-01

    of wafer through-holes the main challenge is to protect the CMOS wafer during etching. In the case of DRIE etching of the wafer through-holes the main challenges are proper insulation of the wafer through-holes, conformal deposition of via metal and structuring of the deposited metal. This thesis discusses...

  5. Stable wafer-carrier system

    Energy Technology Data Exchange (ETDEWEB)

    Rozenzon, Yan; Trujillo, Robert T; Beese, Steven C

    2013-10-22

    One embodiment of the present invention provides a wafer-carrier system used in a deposition chamber for carrying wafers. The wafer-carrier system includes a base susceptor and a top susceptor nested inside the base susceptor with its wafer-mounting side facing the base susceptor's wafer-mounting side, thereby forming a substantially enclosed narrow channel. The base susceptor provides an upward support to the top susceptor.

  6. Handbook of wafer bonding

    CERN Document Server

    Ramm, Peter; Taklo, Maaike M V

    2011-01-01

    Written by an author and editor team from microsystems companies and industry-near research organizations, this handbook and reference presents dependable, first-hand information on bonding technologies.In the first part, researchers from companies and institutions around the world discuss the most reliable and reproducible technologies for the production of bonded wafers. The second part is devoted to current and emerging applications, including microresonators, biosensors and precise measuring devices.

  7. Wafer thinning for high-density, through-wafer interconnects

    Science.gov (United States)

    Wang, Lianwei; Visser, Cassan C. G.; de Boer, Charles R.; Laros, M.; van der Vlist, W.; Groeneweg, J.; Craciun, G.; Sarro, Pasqualina M.

    2003-01-01

    Thinning of micromachined wafers containing trenches and cavities to realize through-chip interconnects is presented. Successful thinning of wafers by lapping and polishing until the cavities previously etched by deep reactive ion etching are reached is demonstrated. The possible causes of damage to the etched structures are investigated. The trapping of particles in the cavities and suitable cleaning procedures to address this issue are studied. The results achieved so far allow further processing of the thinned wafers to form through wafer interconnections by copper electroplating. Further improvement of the quality of thinned surfaces can be achieved by alternative cleaning procedures.

  8. Through-Wafer Optical Interconnects For Multi-Wafer Wafer-Scale Integrated Architectures

    Science.gov (United States)

    Hornak, L. A.; Tewksbury, S. K.; Hatamian, M.; Ligtenberg, A.; Sugla, B.; Franzon, P.

    1986-12-01

    Hybrid mounting of optical components, combined perhaps with integrated optical waveguides and lenses on a large area silicon, wafer-scale integrated (WSI) electronic circuit provides one potential approach to combine advanced electronic and photonic functions. The desire to achieve a high degree of parallelism in multi-wafer WSI-based architectures has stimulated study of three-dimensional interconnect structures obtained by stacking wafer circuit boards and. providing interconnections vertically between wafers over the entire wafer area in addition to planar connections. While presently it is difficult for optical interconnects to compete with electrical interconnects in the wafer plane, it is appropriate to look at vertical optical interconnections between wafer planes since the corresponding conductive structures would be large in area and may impede system repairability. The ability to pass information optically between circuit planes without mechanical electrical contacts offers potential advantages for multi-wafer WSI or other dense three-dimensional architectures. However, while optical waveguides are readily fabricated in the plane of the wafer, waveguiding vertically through the wafer is difficult. If additional processing is required for waveguides or lenses, it should be compatible with standard VLSI processing. This paper presents one straightforward method of meeting this criterion. Using optical device technology operating at wavelengths beyond the ≍1.1μm Si absorption cutoff, low loss, through-wafer propagation between WSI circuit boards can be achieved over the distances of interest (≍1mm) with the interstitial Si wafers as part of the interconnect "free-space" transmission medium. The thickness of existing VLSI layers can be readily adjusted in featureless regions of the wafer to provide antireflection windows such that the transmittance can be raised to ≍77% for n-type and to ≍97% for p-type silicon. Optical interconnect source

  9. Wafer bonding applications and technology

    CERN Document Server

    Gösele, Ulrich

    2004-01-01

    During the past decade direct wafer bonding has developed into a mature materials integration technology. This book presents state-of-the-art reviews of the most important applications of wafer bonding written by experts from industry and academia. The topics include bonding-based fabrication methods of silicon-on-insulator, photonic crystals, VCSELs, SiGe-based FETs, MEMS together with hybrid integration and laser lift-off. The non-specialist will learn about the basics of wafer bonding and its various application areas, while the researcher in the field will find up-to-date information about this fast-moving area, including relevant patent information.

  10. Laser wafering for silicon solar.

    Energy Technology Data Exchange (ETDEWEB)

    Friedmann, Thomas Aquinas; Sweatt, William C.; Jared, Bradley Howell

    2011-03-01

    Current technology cuts solar Si wafers by a wire saw process, resulting in 50% 'kerf' loss when machining silicon from a boule or brick into a wafer. We want to develop a kerf-free laser wafering technology that promises to eliminate such wasteful wire saw processes and achieve up to a ten-fold decrease in the g/W{sub p} (grams/peak watt) polysilicon usage from the starting polysilicon material. Compared to today's technology, this will also reduce costs ({approx}20%), embodied energy, and green-house gas GHG emissions ({approx}50%). We will use short pulse laser illumination sharply focused by a solid immersion lens to produce subsurface damage in silicon such that wafers can be mechanically cleaved from a boule or brick. For this concept to succeed, we will need to develop optics, lasers, cleaving, and high throughput processing technologies capable of producing wafers with thicknesses < 50 {micro}m with high throughput (< 10 sec./wafer). Wafer thickness scaling is the 'Moore's Law' of silicon solar. Our concept will allow solar manufacturers to skip entire generations of scaling and achieve grid parity with commercial electricity rates. Yet, this idea is largely untested and a simple demonstration is needed to provide credibility for a larger scale research and development program. The purpose of this project is to lay the groundwork to demonstrate the feasibility of laser wafering. First, to design and procure on optic train suitable for producing subsurface damage in silicon with the required damage and stress profile to promote lateral cleavage of silicon. Second, to use an existing laser to produce subsurface damage in silicon, and third, to characterize the damage using scanning electron microscopy and confocal Raman spectroscopy mapping.

  11. Laser wafering for silicon solar

    International Nuclear Information System (INIS)

    Friedmann, Thomas Aquinas; Sweatt, William C.; Jared, Bradley Howell

    2011-01-01

    Current technology cuts solar Si wafers by a wire saw process, resulting in 50% 'kerf' loss when machining silicon from a boule or brick into a wafer. We want to develop a kerf-free laser wafering technology that promises to eliminate such wasteful wire saw processes and achieve up to a ten-fold decrease in the g/W p (grams/peak watt) polysilicon usage from the starting polysilicon material. Compared to today's technology, this will also reduce costs (∼20%), embodied energy, and green-house gas GHG emissions (∼50%). We will use short pulse laser illumination sharply focused by a solid immersion lens to produce subsurface damage in silicon such that wafers can be mechanically cleaved from a boule or brick. For this concept to succeed, we will need to develop optics, lasers, cleaving, and high throughput processing technologies capable of producing wafers with thicknesses < 50 (micro)m with high throughput (< 10 sec./wafer). Wafer thickness scaling is the 'Moore's Law' of silicon solar. Our concept will allow solar manufacturers to skip entire generations of scaling and achieve grid parity with commercial electricity rates. Yet, this idea is largely untested and a simple demonstration is needed to provide credibility for a larger scale research and development program. The purpose of this project is to lay the groundwork to demonstrate the feasibility of laser wafering. First, to design and procure on optic train suitable for producing subsurface damage in silicon with the required damage and stress profile to promote lateral cleavage of silicon. Second, to use an existing laser to produce subsurface damage in silicon, and third, to characterize the damage using scanning electron microscopy and confocal Raman spectroscopy mapping.

  12. Bondability of processed glass wafers

    NARCIS (Netherlands)

    Pandraud, G.; Gui, C.; Lambeck, Paul; Pigeon, F.; Parriaux, O.; Gorecki, Christophe

    1999-01-01

    The mechanism of direct bonding at room temperature has been attributed to the short range inter-molecular and inter-atomic attraction forces, such as Van der Waals forces. Consequently, the wafer surface smoothness becomes one of the most critical parameters in this process. High surface roughness

  13. Wafer of Intel Pentium 4 Prescott Chips

    CERN Multimedia

    Silicon wafer with hundreds of Penryn cores (microprocessor). There are around four times as many Prescott chips can be made per wafer than with the previous generation of Northwood-core Pentium 4 processors. It is faster and cheaper.

  14. Wafering economies for industrialization from a wafer manufacturer's viewpoint

    Science.gov (United States)

    Rosenfield, T. P.; Fuerst, F. P.

    1982-01-01

    The key technical limitations which inhibit the lowering of value-added costs for state-of-the-art wafering techniques are assessed. From the best experimental results to date, a projection was made to identify those parts of each system which need to be developed in order to meet or improve upon the value-added cost reduction necessary for $0.70/Wp photovoltaics modules.

  15. Wafer level packaging of MEMS

    International Nuclear Information System (INIS)

    Esashi, Masayoshi

    2008-01-01

    Wafer level packaging plays many important roles for MEMS (micro electro mechanical systems), including cost, yield and reliability. MEMS structures on silicon chips are encapsulated between bonded wafers or by surface micromachining, and electrical interconnections are made from the cavity. Bonding at the interface, such as glass–Si anodic bonding and metal-to-metal bonding, requires electrical interconnection through the lid vias in many cases. On the other hand, lateral electrical interconnections on the surface of the chip are used for bonding with intermediate melting materials, such as low melting point glass and solder. The cavity formed by surface micromachining is made using sacrificial etching, and the openings needed for the sacrificial etching are plugged using deposition sealing methods. Vacuum packaging methods and the structures for electrical feedthrough for the interconnection are discussed in this review. (topical review)

  16. Wafer scale oblique angle plasma etching

    Science.gov (United States)

    Burckel, David Bruce; Jarecki, Jr., Robert L.; Finnegan, Patrick Sean

    2017-05-23

    Wafer scale oblique angle etching of a semiconductor substrate is performed in a conventional plasma etch chamber by using a fixture that supports a multiple number of separate Faraday cages. Each cage is formed to include an angled grid surface and is positioned such that it will be positioned over a separate one of the die locations on the wafer surface when the fixture is placed over the wafer. The presence of the Faraday cages influences the local electric field surrounding each wafer die, re-shaping the local field to be disposed in alignment with the angled grid surface. The re-shaped plasma causes the reactive ions to follow a linear trajectory through the plasma sheath and angled grid surface, ultimately impinging the wafer surface at an angle. The selected geometry of the Faraday cage angled grid surface thus determines the angle at with the reactive ions will impinge the wafer.

  17. Kemoterapi-impraegnerede "wafers" i behandlingen af maligne gliomer i hjernen. Gennemgang af et Cochrane-review

    DEFF Research Database (Denmark)

    Kosteljanetz, Michael; Poulsen, Hans Skovgaard

    2010-01-01

    The present Cochrane review deals with implantation of chemotherapeutic wafers in the surgical cavity after resection of a malignant glioma. The authors found two controlled, randomised studies concerning this treatment modality after first-time surgical treatment and one study dealing with treat...

  18. MEMS packaging with etching and thinning of lid wafer to form lids and expose device wafer bond pads

    Science.gov (United States)

    Chanchani, Rajen; Nordquist, Christopher; Olsson, Roy H; Peterson, Tracy C; Shul, Randy J; Ahlers, Catalina; Plut, Thomas A; Patrizi, Gary A

    2013-12-03

    In wafer-level packaging of microelectromechanical (MEMS) devices a lid wafer is bonded to a MEMS wafer in a predermined aligned relationship. Portions of the lid wafer are removed to separate the lid wafer into lid portions that respectively correspond in alignment with MEMS devices on the MEMS wafer, and to expose areas of the MEMS wafer that respectively contain sets of bond pads respectively coupled to the MEMS devices.

  19. High Speed On-Wafer Characterization Laboratory

    Data.gov (United States)

    Federal Laboratory Consortium — At the High Speed On-Wafer Characterization Laboratory, researchers characterize and model devices operating at terahertz (THz) and millimeter-wave frequencies. The...

  20. Methane production using resin-wafer electrodeionization

    Science.gov (United States)

    Snyder, Seth W; Lin, YuPo; Urgun-Demirtas, Meltem

    2014-03-25

    The present invention provides an efficient method for creating natural gas including the anaerobic digestion of biomass to form biogas, and the electrodeionization of biogas to form natural gas and carbon dioxide using a resin-wafer deionization (RW-EDI) system. The method may be further modified to include a wastewater treatment system and can include a chemical conditioning/dewatering system after the anaerobic digestion system. The RW-EDI system, which includes a cathode and an anode, can either comprise at least one pair of wafers, each a basic and acidic wafer, or at least one wafer comprising of a basic portion and an acidic portion. A final embodiment of the RW-EDI system can include only one basic wafer for creating natural gas.

  1. Industrial Silicon Wafer Solar Cells

    Directory of Open Access Journals (Sweden)

    Dirk-Holger Neuhaus

    2007-01-01

    Full Text Available In 2006, around 86% of all wafer-based silicon solar cells were produced using screen printing to form the silver front and aluminium rear contacts and chemical vapour deposition to grow silicon nitride as the antireflection coating onto the front surface. This paper reviews this dominant solar cell technology looking into state-of-the-art equipment and corresponding processes for each process step. The main efficiency losses of this type of solar cell are analyzed to demonstrate the future efficiency potential of this technology. In research and development, more various advanced solar cell concepts have demonstrated higher efficiencies. The question which arises is “why are new solar cell concepts not transferred into industrial production more frequently?”. We look into the requirements a new solar cell technology has to fulfill to have an advantage over the current approach. Finally, we give an overview of high-efficiency concepts which have already been transferred into industrial production.

  2. The evolution of silicon wafer cleaning technology

    International Nuclear Information System (INIS)

    Kern, W.

    1990-01-01

    The purity of wafer surfaces is an essential requisite for the successful fabrication of VLSI and ULSI silicon circuits. Wafer cleaning chemistry has remained essentially unchanged in the past 25 years and is based on hot alkaline and acidic hydrogen peroxide solutions, a process known as RCA Standard Clean. This is still the primary method used in the industry. What has changed is its implementation with optimized equipment:from simple immersion to centrifugal spraying, megasonic techniques, and enclosed system processing that allow simultaneous removal of both contaminant films and particles. Improvements in wafer drying by use of isopropanol vapor or by slow-pull out of hot deionized water are being investigated. Several alternative cleaning methods are also being tested, including choline solutions, chemical vapor etching, and UV/ozone treatments. The evolution of silicon wafer cleaning processes and technology is traced and reviewed

  3. Modelling deformation and fracture in confectionery wafers

    Science.gov (United States)

    Mohammed, Idris K.; Charalambides, Maria N.; Williams, J. Gordon; Rasburn, John

    2015-01-01

    The aim of this research is to model the deformation and fracture behaviour of brittle wafers often used in chocolate confectionary products. Three point bending and compression experiments were performed on beam and circular disc samples respectively to determine the 'apparent' stress-strain curves in bending and compression. The deformation of the wafer for both these testing types was observed in-situ within an SEM. The wafer is modeled analytically and numerically as a composite material with a core which is more porous than the skins. X-ray tomography was used to generate a three dimensional volume of the wafer microstructure which was then meshed and used for quantitative analysis. A linear elastic material model, with a damage function and element deletion, was used and the XMT generated architecture was loaded in compression. The output from the FE simulations correlates closely to the load-deflection deformation observed experimentally.

  4. Modelling deformation and fracture in confectionery wafers

    Energy Technology Data Exchange (ETDEWEB)

    Mohammed, Idris K.; Charalambides, Maria N.; Williams, J. Gordon; Rasburn, John [Mechanical Engineering Department, Imperial College London, South Kensington, London, SW7 2AZ, United Kingdom and Nestec York Ltd., Nestlé Product Technology Centre, Haxby Road, PO Box 204, York YO91 1XY (United Kingdom)

    2015-01-22

    The aim of this research is to model the deformation and fracture behaviour of brittle wafers often used in chocolate confectionary products. Three point bending and compression experiments were performed on beam and circular disc samples respectively to determine the 'apparent' stress-strain curves in bending and compression. The deformation of the wafer for both these testing types was observed in-situ within an SEM. The wafer is modeled analytically and numerically as a composite material with a core which is more porous than the skins. X-ray tomography was used to generate a three dimensional volume of the wafer microstructure which was then meshed and used for quantitative analysis. A linear elastic material model, with a damage function and element deletion, was used and the XMT generated architecture was loaded in compression. The output from the FE simulations correlates closely to the load-deflection deformation observed experimentally.

  5. Modeling the wafer temperature profile in a multiwafer LPCVD furnace

    Energy Technology Data Exchange (ETDEWEB)

    Badgwell, T.A. [Rice Univ., Houston, TX (United States). Dept. of Chemical Engineering; Trachtenberg, I.; Edgar, T.F. [Univ. of Texas, Austin, TX (United States). Dept. of Chemical Engineering

    1994-01-01

    A mathematical model has been developed to predict wafer temperatures within a hot-wall multiwafer low pressure chemical vapor deposition (LPCVD) reactor. The model predicts both axial (wafer-to-wafer) and radial (across-wafer) temperature profiles. Model predictions compare favorably with in situ wafer temperature measurements described in an earlier paper. Measured axial and radial temperature nonuniformities are explained in terms of radiative heat-transfer effects. A simulation study demonstrates how changes in the outer tube temperature profile and reactor geometry affect wafer temperatures. Reactor design changes which could improve the wafer temperature profile are discussed.

  6. Porous solid ion exchange wafer for immobilizing biomolecules

    Science.gov (United States)

    Arora, Michelle B.; Hestekin, Jamie A.; Lin, YuPo J.; St. Martin, Edward J.; Snyder, Seth W.

    2007-12-11

    A porous solid ion exchange wafer having a combination of a biomolecule capture-resin and an ion-exchange resin forming a charged capture resin within said wafer. Also disclosed is a porous solid ion exchange wafer having a combination of a biomolecule capture-resin and an ion-exchange resin forming a charged capture resin within said wafer containing a biomolecule with a tag. A separate bioreactor is also disclosed incorporating the wafer described above.

  7. X-ray analytics for 450-mm wafer; Roentgenanalytik fuer 450-mm-Wafer

    Energy Technology Data Exchange (ETDEWEB)

    Anon.

    2014-09-15

    The introduction of the 450-mm technology in the wafer fabrication and the further reduction of critical dimensions requires improved X-ray analysis methods. Therefor the PTB has concipated a metrology chamber for the characterization of 450-mm wafers, the crucial element of which is a multi-axis patent-pending manipulator.

  8. Kemoterapi-impraegnerede "wafers" i behandlingen af maligne gliomer i hjernen. Gennemgang af et Cochrane-review

    DEFF Research Database (Denmark)

    Kosteljanetz, Michael; Poulsen, Hans Skovgaard

    2010-01-01

    The present Cochrane review deals with implantation of chemotherapeutic wafers in the surgical cavity after resection of a malignant glioma. The authors found two controlled, randomised studies concerning this treatment modality after first-time surgical treatment and one study dealing...... with treatment of recurrent tumour. An effect was shown in the first with an increase in median survival of 2 months equivalent to the survival seen after standard (concomitant) treatment. No effect was shown in recurrent tumour....

  9. Wafer fab mask qualification techniques and limitations

    Science.gov (United States)

    Poock, Andre; Maelzer, Stephanie; Spence, Chris; Tabery, Cyrus; Lang, Michael; Schnasse, Guido; Peikert, Milko; Bhattacharyya, Kaustuve

    2006-10-01

    Mask inspection and qualification is a must for wafer fabs to ensure and guarantee high and stable yields. Single defect events can easily cause a million dollar loss through a defect duplicating onto the wafer. Several techniques and methods for mask qualification within a wafer fab are known but not all of them are neither used nor understood regarding their limitations. Increasing effort on existing tool platforms is necessary to detect the defects of interest which are at the limit of the tools specification - On the other hand next generation tools are very sensitive and therefore consume only a negligible amount of time for recipe optimization. Knowing the limits of each inspection tool helps to balance between effort and benefit. Masks with programmed defects of 90nm and 65nm design rule were used in order to compare the different available inspection techniques. During the course of this technical work, the authors concentrate mainly on two inspection techniques. The first one inspects the reticle itself using KLA-Tencor's SLF27 (TeraStar) and SL536 (TeraScan) tools. As the reticle gets inspected itself this is the so called "direct" mask defect inspection. The second inspection technique discussed is the "indirect" mask defect inspection which consists of printing the pattern on a blank wafer and use KLA-Tencor's bright-field wafer inspection tool (2xxx series) to inspect the wafer. Data of this work will include description of the techniques, inspection results, defect maps, sensitivity analysis, effort estimation as well as limitations for both techniques for the used design rule.

  10. Wafer level 3-D ICs process technology

    CERN Document Server

    Tan, Chuan Seng; Reif, L Rafael

    2009-01-01

    This book focuses on foundry-based process technology that enables the fabrication of 3-D ICs. The core of the book discusses the technology platform for pre-packaging wafer lever 3-D ICs. However, this book does not include a detailed discussion of 3-D ICs design and 3-D packaging. This is an edited book based on chapters contributed by various experts in the field of wafer-level 3-D ICs process technology. They are from academia, research labs and industry.

  11. High throughput batch wafer handler for 100 to 200 mm wafers

    International Nuclear Information System (INIS)

    Rathmell, R.D.; Raatz, J.E.; Becker, B.L.; Kitchen, R.L.; Luck, T.R.; Decker, J.H.

    1989-01-01

    A new batch processing end station for ion implantation has been developed for wafers of 100 to 200 mm diameter. It usilizes a spinning disk with clampless wafer support. All wafer transport is done with backside handling and is carried out in vacuum. This end station incorporates a new dose control scheme which is able to monitor the incident particle current independently of the charge state of the ions. This technique prevents errors which may be caused by charge exchange between the beam and residual gas. The design and features of this system will be reviewed and the performance to date will be presented. (orig.)

  12. Optimal Wafer Cutting in Shuttle Layout Problems

    DEFF Research Database (Denmark)

    Nisted, Lasse; Pisinger, David; Altman, Avri

    2011-01-01

    . The shuttle layout problem is frequently solved in two phases: first, a floorplan of the shuttle is generated. Then, a cutting plan is found which minimizes the overall number of wafers needed to satisfy the demand of each die type. Since some die types require special production technologies, only compatible...

  13. Controllable laser thermal cleavage of sapphire wafers

    Science.gov (United States)

    Xu, Jiayu; Hu, Hong; Zhuang, Changhui; Ma, Guodong; Han, Junlong; Lei, Yulin

    2018-03-01

    Laser processing of substrates for light-emitting diodes (LEDs) offers advantages over other processing techniques and is therefore an active research area in both industrial and academic sectors. The processing of sapphire wafers is problematic because sapphire is a hard and brittle material. Semiconductor laser scribing processing suffers certain disadvantages that have yet to be overcome, thereby necessitating further investigation. In this work, a platform for controllable laser thermal cleavage was constructed. A sapphire LED wafer was modeled using the finite element method to simulate the thermal and stress distributions under different conditions. A guide groove cut by laser ablation before the cleavage process was observed to guide the crack extension and avoid deviation. The surface and cross section of sapphire wafers processed using controllable laser thermal cleavage were characterized by scanning electron microscopy and optical microscopy, and their morphology was compared to that of wafers processed using stealth dicing. The differences in luminous efficiency between substrates prepared using these two processing methods are explained.

  14. Silicon waveguides produced by wafer bonding

    DEFF Research Database (Denmark)

    Poulsen, Mette; Jensen, Flemming; Bunk, Oliver

    2005-01-01

    X-ray waveguides are successfully produced employing standard silicon technology of UV photolithography and wafer bonding. Contrary to theoretical expectations for similar systems even 100 mu m broad guides of less than 80 nm height do not collapse and can be used as one dimensional waveguides...

  15. Low-cost silicon wafer dicing using a craft cutter

    KAUST Repository

    Fan, Yiqiang

    2014-05-20

    This paper reports a low-cost silicon wafer dicing technique using a commercial craft cutter. The 4-inch silicon wafers were scribed using a crafter cutter with a mounted diamond blade. The pre-programmed automated process can reach a minimum die feature of 3 mm by 3 mm. We performed this scribing process on the top polished surface of a silicon wafer; we also created a scribing method for the back-unpolished surface in order to protect the structures on the wafer during scribing. Compared with other wafer dicing methods, our proposed dicing technique is extremely low cost (lower than $1,000), and suitable for silicon wafer dicing in microelectromechanical or microfluidic fields, which usually have a relatively large die dimension. The proposed dicing technique is also usable for dicing multiple project wafers, a process where dies of different dimensions are diced on the same wafer.

  16. Wafer integrated micro-scale concentrating photovoltaics

    Science.gov (United States)

    Gu, Tian; Li, Duanhui; Li, Lan; Jared, Bradley; Keeler, Gordon; Miller, Bill; Sweatt, William; Paap, Scott; Saavedra, Michael; Das, Ujjwal; Hegedus, Steve; Tauke-Pedretti, Anna; Hu, Juejun

    2017-09-01

    Recent development of a novel micro-scale PV/CPV technology is presented. The Wafer Integrated Micro-scale PV approach (WPV) seamlessly integrates multijunction micro-cells with a multi-functional silicon platform that provides optical micro-concentration, hybrid photovoltaic, and mechanical micro-assembly. The wafer-embedded micro-concentrating elements is shown to considerably improve the concentration-acceptance-angle product, potentially leading to dramatically reduced module materials and fabrication costs, sufficient angular tolerance for low-cost trackers, and an ultra-compact optical architecture, which makes the WPV module compatible with commercial flat panel infrastructures. The PV/CPV hybrid architecture further allows the collection of both direct and diffuse sunlight, thus extending the geographic and market domains for cost-effective PV system deployment. The WPV approach can potentially benefits from both the high performance of multijunction cells and the low cost of flat plate Si PV systems.

  17. Devices using resin wafers and applications thereof

    Science.gov (United States)

    Lin, YuPo J [Naperville, IL; Henry, Michael P [Batavia, IL; Snyder, Seth W [Lincolnwood, IL; Martin, Edward [Libertyville, IL; Arora, Michelle [Woodridge, IL; de la Garza, Linda [Woodridge, IL

    2009-03-24

    Devices incorporating a thin wafer of electrically and ionically conductive porous material made by the method of introducing a mixture of a thermoplastic binder and one or more of anion exchange moieties or cation exchange moieties or mixtures thereof and/or one or more of a protein capture resin and an electrically conductive material into a mold. The mixture is subjected to temperatures in the range of from about 60.degree. C. to about 170.degree. C. at pressures in the range of from about 0 to about 500 psig for a time in the range of from about 1 to about 240 minutes to form thin wafers. Devices include electrodeionization and separative bioreactors in the production of organic and amino acids, alcohols or esters for regenerating cofactors in enzymes and microbial cells.

  18. Optical cavity furnace for semiconductor wafer processing

    Science.gov (United States)

    Sopori, Bhushan L.

    2014-08-05

    An optical cavity furnace 10 having multiple optical energy sources 12 associated with an optical cavity 18 of the furnace. The multiple optical energy sources 12 may be lamps or other devices suitable for producing an appropriate level of optical energy. The optical cavity furnace 10 may also include one or more reflectors 14 and one or more walls 16 associated with the optical energy sources 12 such that the reflectors 14 and walls 16 define the optical cavity 18. The walls 16 may have any desired configuration or shape to enhance operation of the furnace as an optical cavity 18. The optical energy sources 12 may be positioned at any location with respect to the reflectors 14 and walls defining the optical cavity. The optical cavity furnace 10 may further include a semiconductor wafer transport system 22 for transporting one or more semiconductor wafers 20 through the optical cavity.

  19. Carbon dioxide capture using resin-wafer electrodeionization

    Energy Technology Data Exchange (ETDEWEB)

    Lin, YuPo J.; Snyder, Seth W.; Trachtenberg, Michael S.; Cowan, Robert M.; Datta, Saurav

    2015-09-08

    The present invention provides a resin-wafer electrodeionization (RW-EDI) apparatus including cathode and anode electrodes separated by a plurality of porous solid ion exchange resin wafers, which when in use are filled with an aqueous fluid. The apparatus includes one or more wafers comprising a basic ion exchange medium, and preferably includes one or more wafers comprising an acidic ion exchange medium. The wafers are separated from one another by ion exchange membranes. The fluid within the acidic and/or basic ion exchange wafers preferably includes, or is in contact with, a carbonic anhydrase (CA) enzyme to facilitate conversion of bicarbonate ion to carbon dioxide within the acidic medium. A pH suitable for exchange of CO.sub.2 is electrochemically maintained within the basic and acidic ion exchange wafers by applying an electric potential across the cathode and anode.

  20. Wafer-scale micro-optics fabrication

    Science.gov (United States)

    Voelkel, Reinhard

    2012-07-01

    Micro-optics is an indispensable key enabling technology for many products and applications today. Probably the most prestigious examples are the diffractive light shaping elements used in high-end DUV lithography steppers. Highly-efficient refractive and diffractive micro-optical elements are used for precise beam and pupil shaping. Micro-optics had a major impact on the reduction of aberrations and diffraction effects in projection lithography, allowing a resolution enhancement from 250 nm to 45 nm within the past decade. Micro-optics also plays a decisive role in medical devices (endoscopes, ophthalmology), in all laser-based devices and fiber communication networks, bringing high-speed internet to our homes. Even our modern smart phones contain a variety of micro-optical elements. For example, LED flash light shaping elements, the secondary camera, ambient light and proximity sensors. Wherever light is involved, micro-optics offers the chance to further miniaturize a device, to improve its performance, or to reduce manufacturing and packaging costs. Wafer-scale micro-optics fabrication is based on technology established by the semiconductor industry. Thousands of components are fabricated in parallel on a wafer. This review paper recapitulates major steps and inventions in wafer-scale micro-optics technology. The state-of-the-art of fabrication, testing and packaging technology is summarized.

  1. Lamb wave propagation in monocrystalline silicon wafers.

    Science.gov (United States)

    Fromme, Paul; Pizzolato, Marco; Robyr, Jean-Luc; Masserey, Bernard

    2018-01-01

    Monocrystalline silicon wafers are widely used in the photovoltaic industry for solar panels with high conversion efficiency. Guided ultrasonic waves offer the potential to efficiently detect micro-cracks in the thin wafers. Previous studies of ultrasonic wave propagation in silicon focused on effects of material anisotropy on bulk ultrasonic waves, but the dependence of the wave propagation characteristics on the material anisotropy is not well understood for Lamb waves. The phase slowness and beam skewing of the two fundamental Lamb wave modes A 0 and S 0 were investigated. Experimental measurements using contact wedge transducer excitation and laser measurement were conducted. Good agreement was found between the theoretically calculated angular dependency of the phase slowness and measurements for different propagation directions relative to the crystal orientation. Significant wave skew and beam widening was observed experimentally due to the anisotropy, especially for the S 0 mode. Explicit finite element simulations were conducted to visualize and quantify the guided wave beam skew. Good agreement was found for the A 0 mode, but a systematic discrepancy was observed for the S 0 mode. These effects need to be considered for the non-destructive testing of wafers using guided waves.

  2. Wafer level test solutions for IR sensors

    Science.gov (United States)

    Giessmann, Sebastian; Werner, Frank-Michael

    2014-05-01

    Wafer probers provide an established platform for performing electrical measurements at wafer level for CMOS and similar process technologies. For testing IR sensors, the requirements are beyond the standard prober capabilities. This presentation will give an overview about state of the art IR sensor probing systems reaching from flexible engineering solutions to automated production needs. Cooled sensors typically need to be tested at a target temperature below 80 K. Not only is the device temperature important but also the surrounding environment is required to prevent background radiation from reaching the device under test. To achieve that, a cryogenic shield is protecting the movable chuck. By operating that shield to attract residual gases inside the chamber, a completely contamination-free test environment can be guaranteed. The use of special black coatings are furthermore supporting the removal of stray light. Typically, probe card needles are operating at ambient (room) temperature when connecting to the wafer. To avoid the entrance of heat, which can result in distorted measurements, the probe card is fully embedded into the cryogenic shield. A shutter system, located above the probe field, is designed to switch between the microscope view to align the sensor under the needles and the test relevant setup. This includes a completely closed position to take dark current measurements. Another position holds a possible filter glass with the required aperture opening. The necessary infrared sources to stimulate the device are located above.

  3. On the evolution of wafer level cameras

    Science.gov (United States)

    Welch, H.

    2011-02-01

    The introduction of small cost effective cameras based on CMOS image sensor technology has played an important role in the revolution in mobile devices of the last 10 years. Wafer-based optics manufacturing leverages the same fabrication equipment used to produce CMOS sensors. The natural integration of these two technologies allows the mass production of very low cost surface mount cameras that can fit into ever thinner mobile devices. Nano Imprint Lithography (NIL) equipment has been adapted to make precision aspheres that can be stacked using wafer bonding techniques to produce multi-element lens assemblies. This, coupled with advances in mastering technology, allows arrays of lenses with prescriptions not previously possible. A primary motivation for these methods is that it allows the consolidation of the supply chain. Image sensor manufacturers envision creating optics by simply adding layers to their existing sensor fabrication lines. Results thus far have been promising. The current alternative techniques for creating VGA cameras are discussed as well as the prime cost drivers for lens to sensor integration. Higher resolution cameras face particularly difficult challenges, but can greatly simplify the critical tilt and focus steps needed to assemble cameras that produce quality images. Finally, we discuss the future of wafer-level cameras and explore several of the novel concepts made possible by the manufacturing advantages of photolithography.

  4. Cost-Efficient Wafer-Level Capping for MEMS and Imaging Sensors by Adhesive Wafer Bonding

    Directory of Open Access Journals (Sweden)

    Simon J. Bleiker

    2016-10-01

    Full Text Available Device encapsulation and packaging often constitutes a substantial part of the fabrication cost of micro electro-mechanical systems (MEMS transducers and imaging sensor devices. In this paper, we propose a simple and cost-effective wafer-level capping method that utilizes a limited number of highly standardized process steps as well as low-cost materials. The proposed capping process is based on low-temperature adhesive wafer bonding, which ensures full complementary metal-oxide-semiconductor (CMOS compatibility. All necessary fabrication steps for the wafer bonding, such as cavity formation and deposition of the adhesive, are performed on the capping substrate. The polymer adhesive is deposited by spray-coating on the capping wafer containing the cavities. Thus, no lithographic patterning of the polymer adhesive is needed, and material waste is minimized. Furthermore, this process does not require any additional fabrication steps on the device wafer, which lowers the process complexity and fabrication costs. We demonstrate the proposed capping method by packaging two different MEMS devices. The two MEMS devices include a vibration sensor and an acceleration switch, which employ two different electrical interconnection schemes. The experimental results show wafer-level capping with excellent bond quality due to the re-flow behavior of the polymer adhesive. No impediment to the functionality of the MEMS devices was observed, which indicates that the encapsulation does not introduce significant tensile nor compressive stresses. Thus, we present a highly versatile, robust, and cost-efficient capping method for components such as MEMS and imaging sensors.

  5. Wafer-scale pixelated detector system

    Science.gov (United States)

    Fahim, Farah; Deptuch, Grzegorz; Zimmerman, Tom

    2017-10-17

    A large area, gapless, detection system comprises at least one sensor; an interposer operably connected to the at least one sensor; and at least one application specific integrated circuit operably connected to the sensor via the interposer wherein the detection system provides high dynamic range while maintaining small pixel area and low power dissipation. Thereby the invention provides methods and systems for a wafer-scale gapless and seamless detector systems with small pixels, which have both high dynamic range and low power dissipation.

  6. The role of Gliadel wafers in the treatment of newly diagnosed GBM: a meta-analysis

    Directory of Open Access Journals (Sweden)

    Xing WK

    2015-06-01

    Full Text Available Wei-kang Xing,1 Chuan Shao,2 Zhen-yu Qi,1 Chao Yang,1 Zhong Wang1 1Department of Neurosurgery, The First Affiliated Hospital of Soochow University, Suzhou, Jiangsu, 2Department of Neurosurgery, The Second Clinical Medical College of North Sichuan Medical College, Nanchong, Sichuan, People’s Republic of China Background: Standard treatment for high-grade glioma (HGG includes surgery followed by radiotherapy and/or chemotherapy. Insertion of carmustine wafers into the resection cavity as a treatment for malignant glioma is currently a controversial topic among neurosurgeons. Our meta-analysis focused on whether carmustine wafer treatment could significantly benefit the survival of patients with newly diagnosed glioblastoma multiforme (GBM.Method: We searched the PubMed and Web of Science databases without any restrictions on language using the keywords “Gliadel wafers”, “carmustine wafers”, “BCNU wafers”, or “interstitial chemotherapy” in newly diagnosed GBM for the period from January 1990 to March 2015. Randomized controlled trials (RCTs and cohort studies/clinical trials that compared treatments designed with and without carmustine wafers and which reported overall survival or hazard ratio (HR or survival curves were included in this study. Moreover, the statistical analysis was conducted by the STATA 12.0 software.Results: Six studies including two RCTs and four cohort studies, enrolling a total of 513 patients (223 with and 290 without carmustine wafers, matched the selection criteria. Carmustine wafers showed a strong advantage when pooling all the included studies (HR =0.63, 95% confidence interval (CI =0.49–0.81; P=0.019. However, the two RCTs did not show a statistical increase in survival in the group with carmustine wafer compared to the group without it (HR =0.51, 95% CI =0.18–1.41; P=0.426, while the cohort studies demonstrated a significant survival increase (HR =0.59, 95% CI =0.44–0.79; P<0.0001.Conclusion

  7. Sol-gel bonding of silicon wafers

    International Nuclear Information System (INIS)

    Barbe, C.J.; Cassidy, D.J.; Triani, G.; Latella, B.A.; Mitchell, D.R.G.; Finnie, K.S.; Short, K.; Bartlett, J.R.; Woolfrey, J.L.; Collins, G.A.

    2005-01-01

    Sol-gel bonds have been produced between smooth, clean silicon substrates by spin-coating solutions containing partially hydrolysed silicon alkoxides. The two coated substrates were assembled and the resulting sandwich fired at temperatures ranging from 60 to 600 deg. C. The sol-gel coatings were characterised using attenuated total reflectance Fourier transform infrared spectroscopy, ellipsometry, and atomic force microscopy, while the corresponding bonded specimens were investigated using scanning electron microscopy and cross-sectional transmission electron microscopy. Mechanical properties were characterised using both microindentation and tensile testing. Bonding of silicon wafers has been successfully achieved at temperatures as low as 60 deg. C. At 300 deg. C, the interfacial fracture energy was 1.55 J/m 2 . At 600 deg. C, sol-gel bonding provided superior interfacial fracture energy over classical hydrophilic bonding (3.4 J/m 2 vs. 1.5 J/m 2 ). The increase in the interfacial fracture energy is related to the increase in film density due to the sintering of the sol-gel interface with increasing temperature. The superior interfacial fracture energy obtained by sol-gel bonding at low temperature is due to the formation of an interfacial layer, which chemically bonds the two sol-gel coatings on each wafer. Application of a tensile stress on the resulting bond leads to fracture of the samples at the silicon/sol-gel interface

  8. 1366 Direct Wafer: Demolishing the Cost Barrier for Silicon Photovoltaics

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, Adam [1366 Technologies

    2013-08-30

    The goal of 1366 Direct Wafer™ is to drastically reduce the cost of silicon-based PV by eliminating the cost barrier imposed by sawn wafers. The key characteristics of Direct Wafer are 1) kerf-free, 156-mm standard silicon wafers 2) high throughput for very low CAPEX and rapid scale up. Together, these characteristics will allow Direct Wafer™ to become the new standard for silicon PV wafers and will enable terawatt-scale PV – a prospect that may not be possible with sawn wafers. Our single, high-throughput step will replace the expensive and rate-limiting process steps of ingot casting and sawing, thereby enabling drastically lower wafer cost. This High-Impact PV Supply Chain project addressed the challenges of scaling Direct Wafer technology for cost-effective, high-throughput production of commercially viable 156 mm wafers. The Direct Wafer process is inherently simple and offers the potential for very low production cost, but to realize this, it is necessary to demonstrate production of wafers at high-throughput that meet customer specifications. At the start of the program, 1366 had demonstrated (with ARPA-E funding) increases in solar cell efficiency from 10% to 15.9% on small area (20cm2), scaling wafer size up to the industry standard 156mm, and demonstrated initial cell efficiency on larger wafers of 13.5%. During this program, the throughput of the Direct Wafer furnace was increased by more than 10X, simultaneous with quality improvements to meet early customer specifications. Dedicated equipment for laser trimming of wafers and measurement methods were developed to feedback key quality metrics to improve the process and equipment. Subsequent operations served both to determine key operating metrics affecting cost, as well as generating sample product that was used for developing downstream processing including texture and interaction with standard cell processing. Dramatic price drops for silicon wafers raised the bar significantly, but the

  9. Si-to-Si wafer bonding using evaporated glass

    DEFF Research Database (Denmark)

    Reus, Roger De; Lindahl, M.

    1997-01-01

    Anodic bonding of Si to Si four inch wafers using evaporated glass was performed in air at temperatures ranging from 300°C to 450°C. Although annealing of Si/glass structures around 340°C for 15 minutes eliminates stress, the bonded wafer pairs exhibit compressive stress. Pull testing revealed...

  10. Patterned wafer geometry grouping for improved overlay control

    Science.gov (United States)

    Lee, Honggoo; Han, Sangjun; Woo, Jaeson; Park, Junbeom; Song, Changrock; Anis, Fatima; Vukkadala, Pradeep; Jeon, Sanghuck; Choi, DongSub; Huang, Kevin; Heo, Hoyoung; Smith, Mark D.; Robinson, John C.

    2017-03-01

    Process-induced overlay errors from outside the litho cell have become a significant contributor to the overlay error budget including non-uniform wafer stress. Previous studies have shown the correlation between process-induced stress and overlay and the opportunity for improvement in process control, including the use of patterned wafer geometry (PWG) metrology to reduce stress-induced overlay signatures. Key challenges of volume semiconductor manufacturing are how to improve not only the magnitude of these signatures, but also the wafer to wafer variability. This work involves a novel technique of using PWG metrology to provide improved litho-control by wafer-level grouping based on incoming process induced overlay, relevant for both 3D NAND and DRAM. Examples shown in this study are from 19 nm DRAM manufacturing.

  11. Semiconductor industry wafer fab exhaust management

    CERN Document Server

    Sherer, Michael J

    2005-01-01

    Given the myriad exhaust compounds and the corresponding problems that they can pose in an exhaust management system, the proper choice of such systems is a complex task. Presenting the fundamentals, technical details, and general solutions to real-world problems, Semiconductor Industry: Wafer Fab Exhaust Management offers practical guidance on selecting an appropriate system for a given application. Using examples that provide a clear understanding of the concepts discussed, Sherer covers facility layout, support facilities operations, and semiconductor process equipment, followed by exhaust types and challenges. He reviews exhaust point-of-use devices and exhaust line requirements needed between process equipment and the centralized exhaust system. The book includes information on wet scrubbers for a centralized acid exhaust system and a centralized ammonia exhaust system and on centralized equipment to control volatile organic compounds. It concludes with a chapter devoted to emergency releases and a separ...

  12. Fluorine-enhanced low-temperature wafer bonding of native-oxide covered Si wafers

    Science.gov (United States)

    Tong, Q.-Y.; Gan, Q.; Fountain, G.; Enquist, P.; Scholz, R.; Gösele, U.

    2004-10-01

    The bonding energy of bonded native-oxide-covered silicon wafers treated in the HNO3/H2O/HF or the HNO3/HF solution prior to room-temperature contact is significantly higher than bonded standard RCA1 cleaned wafer pairs after low-temperature annealing. The bonding energy reaches over 2000mJ/m2 after annealing at 100 °C. The very slight etching and fluorine in the chemically grown oxide are believed to be the main contributors to the enhanced bonding energy. Transmission-electron-microscopic images have shown that the chemically formed native oxide at bonding interface is embedded with many flake-like cavities. The cavities can absorb the by-products of the interfacial reactions that result in covalent bond formation at low temperatures allowing the strong bond to be retained.

  13. Design Study of Wafer Seals for Future Hypersonic Vehicles

    Science.gov (United States)

    Dunlap, Patrick H.; Finkbeiner, Joshua R.; Steinetz, Bruce M.; DeMange, Jeffrey J.

    2005-01-01

    Future hypersonic vehicles require high temperature, dynamic seals in advanced hypersonic engines and on the vehicle airframe to seal the perimeters of movable panels, flaps, and doors. Current seals do not meet the demanding requirements of these applications, so NASA Glenn Research Center is developing improved designs to overcome these shortfalls. An advanced ceramic wafer seal design has shown promise in meeting these needs. Results from a design of experiments study performed on this seal revealed that several installation variables played a role in determining the amount of leakage past the seals. Lower leakage rates were achieved by using a tighter groove width around the seals, a higher seal preload, a tighter wafer height tolerance, and a looser groove length. During flow testing, a seal activating pressure acting behind the wafers combined with simulated vibrations to seat the seals more effectively against the sealing surface and produce lower leakage rates. A seal geometry study revealed comparable leakage for full-scale wafers with 0.125 and 0.25 in. thicknesses. For applications in which lower part counts are desired, fewer 0.25-in.-thick wafers may be able to be used in place of 0.125-in.-thick wafers while achieving similar performance. Tests performed on wafers with a rounded edge (0.5 in. radius) in contact with the sealing surface resulted in flow rates twice as high as those for wafers with a flat edge. Half-size wafers had leakage rates approximately three times higher than those for full-size wafers.

  14. Capacitive micromachined ultrasonic transducers with through-wafer interconnects

    Science.gov (United States)

    Zhuang, Xuefeng

    Capacitive micromachined ultrasonic transducer (CMUT) is a promising candidate for making ultrasound transducer arrays for applications such as 3D medical ultrasound, non-destructive evaluation and chemical sensing. Advantages of CMUTs over traditional piezoelectric transducers include low-cost batch fabrication, wide bandwidth, and ability to fabricate arrays with broad operation frequency range and different geometric configurations on a single wafer. When incorporated with through-wafer interconnects, a CMUT array can be directly integrated with a front-end integrated circuit (IC) to achieve compact packaging and to mitigate the effects of the parasitic capacitance from the connection cables. Through-wafer via is the existing interconnect scheme for CMUT arrays, and many other types of micro-electro-mechanical system (MEMS) devices. However, to date, no successful through-wafer via fabrication technique compatible with the wafer-bonding method of making CMUT arrays has been demonstrated. The through-wafer via fabrication steps degrade the surface conditions of the wafer, reduce the radius of curvature, thus making it difficult to bond. This work focuses on new through-wafer interconnect techniques that are compatible with common MEMS fabrication techniques, including both surface-micromachining and direct wafer-to-wafer fusion bonding. In this dissertation, first, a through-wafer via interconnect technique with improved characteristics is presented. Then, two implementations of through-wafer trench isolation are demonstrated. The through-wafer trench methods differ from the through-wafer vias in that the electrical conduction is through the bulk silicon instead of the conductor in the vias. In the first implementation, a carrier wafer is used to provide mechanical support; in the second, mechanical support is provided by a silicon frame structure embedded inside the isolation trenches. Both implementations reduce fabrication complexity compared to the through-wafer

  15. Wafer-Level Vacuum Packaging of Smart Sensors.

    Science.gov (United States)

    Hilton, Allan; Temple, Dorota S

    2016-10-31

    The reach and impact of the Internet of Things will depend on the availability of low-cost, smart sensors-"low cost" for ubiquitous presence, and "smart" for connectivity and autonomy. By using wafer-level processes not only for the smart sensor fabrication and integration, but also for packaging, we can further greatly reduce the cost of sensor components and systems as well as further decrease their size and weight. This paper reviews the state-of-the-art in the wafer-level vacuum packaging technology of smart sensors. We describe the processes needed to create the wafer-scale vacuum microchambers, focusing on approaches that involve metal seals and that are compatible with the thermal budget of complementary metal-oxide semiconductor (CMOS) integrated circuits. We review choices of seal materials and structures that are available to a device designer, and present techniques used for the fabrication of metal seals on device and window wafers. We also analyze the deposition and activation of thin film getters needed to maintain vacuum in the ultra-small chambers, and the wafer-to-wafer bonding processes that form the hermetic seal. We discuss inherent trade-offs and challenges of each seal material set and the corresponding bonding processes. Finally, we identify areas for further research that could help broaden implementations of the wafer-level vacuum packaging technology.

  16. Wafer-Level Vacuum Packaging of Smart Sensors

    Directory of Open Access Journals (Sweden)

    Allan Hilton

    2016-10-01

    Full Text Available The reach and impact of the Internet of Things will depend on the availability of low-cost, smart sensors—“low cost” for ubiquitous presence, and “smart” for connectivity and autonomy. By using wafer-level processes not only for the smart sensor fabrication and integration, but also for packaging, we can further greatly reduce the cost of sensor components and systems as well as further decrease their size and weight. This paper reviews the state-of-the-art in the wafer-level vacuum packaging technology of smart sensors. We describe the processes needed to create the wafer-scale vacuum microchambers, focusing on approaches that involve metal seals and that are compatible with the thermal budget of complementary metal-oxide semiconductor (CMOS integrated circuits. We review choices of seal materials and structures that are available to a device designer, and present techniques used for the fabrication of metal seals on device and window wafers. We also analyze the deposition and activation of thin film getters needed to maintain vacuum in the ultra-small chambers, and the wafer-to-wafer bonding processes that form the hermetic seal. We discuss inherent trade-offs and challenges of each seal material set and the corresponding bonding processes. Finally, we identify areas for further research that could help broaden implementations of the wafer-level vacuum packaging technology.

  17. Small bowel resection

    Science.gov (United States)

    ... Ileostomy and your diet Ileostomy - caring for your stoma Ileostomy - changing your pouch Ileostomy - discharge Ileostomy - what to ask your doctor Low-fiber diet Preventing falls Small bowel resection - discharge Surgical wound care - open Types of ileostomy Ulcerative colitis - discharge When ...

  18. Large bowel resection

    Science.gov (United States)

    ... Ileostomy and your diet Ileostomy - caring for your stoma Ileostomy - changing your pouch Ileostomy - discharge Ileostomy - what to ask your doctor Large bowel resection - discharge Low-fiber diet Preventing falls Surgical wound care - open Types of ileostomy When you have nausea ...

  19. The uses of Man-Made diamond in wafering applications

    Science.gov (United States)

    Fallon, D. B.

    1982-01-01

    The continuing, rapid growth of the semiconductor industry requires the involvement of several specialized industries in the development of special products geared toward the unique requirements of this new industry. A specialized manufactured diamond to meet various material removal needs was discussed. The area of silicon wafer slicing has presented yet anothr challenge and it is met most effectively. The history, operation, and performance of Man-Made diamond and particularly as applied to silicon wafer slicing is discussed. Product development is underway to come up with a diamond specifically for sawing silicon wafers on an electroplated blade.

  20. Feature extraction of the wafer probe marks in IC packaging

    Science.gov (United States)

    Tsai, Cheng-Yu; Lin, Chia-Te; Kao, Chen-Ting; Wang, Chau-Shing

    2017-12-01

    This paper presents an image processing approach to extract six features of the probe mark on semiconductor wafer pads. The electrical characteristics of the chip pad must be tested using a probing needle before wire-bonding to the wafer. However, this test leaves probe marks on the pad. A large probe mark area results in poor adhesion forces at the bond ball of the pad, thus leading to undesirable products. In this paper, we present a method to extract six features of the wafer probe marks in IC packaging for further digital image processing.

  1. Wafer-bonded 2-D CMUT arrays incorporating through-wafer trench-isolated interconnects with a supporting frame.

    Science.gov (United States)

    Zhuang, Xuefeng; Wygant, Ira O; Lin, Der-Song; Kupnik, Mario; Oralkan, Omer; Khuri-Yakub, Butrus T

    2009-01-01

    This paper reports on wafer-bonded, fully populated 2-D capacitive micromachined ultrasonic transducer (CMUT) arrays. To date, no successful through-wafer via fabrication technique has been demonstrated that is compatible with the wafer-bonding method of making CMUT arrays. As an alternative to through-wafer vias, trench isolation with a supporting frame is incorporated into the 2-D arrays to provide through-wafer electrical connections. The CMUT arrays are built on a silicon-on-insulator (SOI) wafer, and all electrical connections to the array elements are brought to the back side of the wafer through the highly conductive silicon substrate. Neighboring array elements are separated by trenches on both the device layer and the bulk silicon. A mesh frame structure, providing mechanical support, is embedded between silicon pillars, which electrically connect to individual elements. We successfully fabricated a 16 x 16-element 2-D CMUT array using wafer bonding with a yield of 100%. Across the array, the pulse-echo amplitude distribution is uniform (rho = 6.6% of the mean amplitude). In one design, we measured a center frequency of 7.6 MHz, a peak-to-peak output pressure of 2.9 MPa at the transducer surface, and a 3-dB fractional bandwidth of 95%. Volumetric ultrasound imaging was demonstrated by chip-to-chip bonding one of the fabricated 2-D arrays to a custom-designed integrated circuit (IC). This study shows that through-wafer trench-isolation with a supporting frame is a viable solution for providing electrical interconnects to CMUT elements and that 2-D arrays fabricated using waferbonding deliver good performance.

  2. Sol-gel bonding of silicon wafers

    International Nuclear Information System (INIS)

    Barbe, C.J.; Cassidy, D.J.; Triani, G.; Latella, B.A.; Mitchell, D.R.G.; Finnie, K.S.; Bartlett, J.R.; Woolfrey, J.L.; Collins, G.A.

    2005-01-01

    Low temperature bonding of silicon wafers was achieved using sol-gel technology. The initial sol-gel chemistry of the coating solution was found to influence the mechanical properties of the resulting bonds. More precisely, the influence of parameters such as the alkoxide concentration, water-to-alkoxide molar ratio, pH, and solution aging on the final bond morphologies and interfacial fracture energy was studied. The thickness and density of the sol-gel coating were characterised using ellipsometry. The corresponding bonded specimens were investigated using attenuated total reflectance Fourier transformed infrared spectroscopy to monitor their chemical composition, infrared imaging to control bond integrity, and cross-sectional transmission electron microscopy to study their microstructure. Their interfacial fracture energy was measured using microindentation. An optimum water-to-alkoxide molar ratio of 10 and hydrolysis water at pH = 2 were found. Such conditions led to relatively dense films (> 90%), resulting in bonds with a fracture energy of 3.5 J/m 2 , significantly higher than those obtained using classical hydrophilic bonding (typically 1.5-2.5 J/m 2 ). Ageing of the coating solution was found to decrease the bond strength

  3. High Performance Wafer-Based Capillary Electrochromatography, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Los Gatos Research proposes to develop wafer-based capillary electrochromatography for lab-on-a-chip (LOC) applications. These microfluidic devices will be...

  4. Automated reticle inspection data analysis for wafer fabs

    Science.gov (United States)

    Summers, Derek; Chen, Gong; Reese, Bryan; Hutchinson, Trent; Liesching, Marcus; Ying, Hai; Dover, Russell

    2009-04-01

    To minimize potential wafer yield loss due to mask defects, most wafer fabs implement some form of reticle inspection system to monitor photomask quality in high-volume wafer manufacturing environments. Traditionally, experienced operators review reticle defects found by an inspection tool and then manually classify each defect as 'pass, warn, or fail' based on its size and location. However, in the event reticle defects are suspected of causing repeating wafer defects on a completed wafer, potential defects on all associated reticles must be manually searched on a layer-by-layer basis in an effort to identify the reticle responsible for the wafer yield loss. This 'problem reticle' search process is a very tedious and time-consuming task and may cause extended manufacturing line-down situations. Often times, Process Engineers and other team members need to manually investigate several reticle inspection reports to determine if yield loss can be tied to a specific layer. Because of the very nature of this detailed work, calculation errors may occur resulting in an incorrect root cause analysis effort. These delays waste valuable resources that could be spent working on other more productive activities. This paper examines an automated software solution for converting KLA-Tencor reticle inspection defect maps into a format compatible with KLA-Tencor's Klarity Defect(R) data analysis database. The objective is to use the graphical charting capabilities of Klarity Defect to reveal a clearer understanding of defect trends for individual reticle layers or entire mask sets. Automated analysis features include reticle defect count trend analysis and potentially stacking reticle defect maps for signature analysis against wafer inspection defect data. Other possible benefits include optimizing reticle inspection sample plans in an effort to support "lean manufacturing" initiatives for wafer fabs.

  5. One step automated unpatterned wafer defect detection and classification

    International Nuclear Information System (INIS)

    Dou Lie; Kesler, Daniel; Bruno, William; Monjak, Charles; Hunt, Jim

    1998-01-01

    Automated detection and classification of crystalline defects on micro-grade silicon wafers is extremely important for integrated circuit (IC) device yield. High training cost, limited capability of classifying defects, increasing possibility of contamination, and unexpected human mistakes necessitate the need to replace the human visual inspection with automated defect inspection. The Laser Scanning Surface Inspection Systems (SSISs) equipped with the Reconvergent Specular Detection (RSD) apparatus are widely used for final wafer inspection. RSD, more commonly known as light channel detection (LC), is capable of detecting and classifying material defects by analyzing information from two independent phenomena, light scattering and reflecting. This paper presents a new technique including a new type of light channel detector to detect and classify wafer surface defects such as slipline dislocation, Epi spikes, Pits, and dimples. The optical system to study this technique consists of a particle scanner to detect and quantify light scattering events from contaminants on the wafer surface and a RSD apparatus (silicon photo detector). Compared with the light channel detector presently used in the wafer fabs, this new light channel technique provides higher sensitivity for small defect detection and more defect scattering signatures for defect classification. Epi protrusions (mounds and spikes), slip dislocations, voids, dimples, and some other common defect features and contamination on silicon wafers are studied using this equipment. The results are compared quantitatively with that of human visual inspection and confirmed by microscope or AFM. This new light channel technology could provide the real future solution to the wafer manufacturing industry for fully automated wafer inspection and defect characterization

  6. Development of Megasonic cleaning for silicon wafers. Final report

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, A.

    1980-09-01

    The major goals to develop a cleaning and drying system for processing at least 2500 three-in.-diameter wafers per hour and to reduce the process cost were achieved. The new system consists of an ammonia-hydrogen peroxide bath in which both surfaces of 3/32-in.-spaced, ion-implanted wafers are cleaned in quartz carriers moved on a belt past two pairs of Megasonic transducers. The wafers are dried in the novel room-temperature, high-velocity air dryer in the same carriers used for annealing. A new laser scanner was used effectively to monitor the cleaning ability on a sampling basis. The following factors contribute to the improved effectiveness of the process: (1) recirculation and filtration of the cleaning solution permit it to be used for at least 100,000 wafers with only a relatively small amount of chemical make-up before discarding; (2) uniform cleanliness is achieved because both sides of the wafer are Megasonically scrubbed to remove particulate impurities; (3) the novel dryer permits wafers to be dried in a high-velocity room-temperature air stream on a moving belt in their quartz carriers; and (4) the personnel safety of such a system is excellent and waste disposal has no adverse ecological impact. With the addition of mechanical transfer arms, two systems like the one developed will produce enough cleaned wafers for a 30-MW/year production facility. A projected scale-up well within the existing technology would permit a system to be assembled that produces about 12,745 wafers per hour; about 11 such systems, each occupying about 110 square feet, would be needed for each cleaning stage of a 500-MW/year production facility.

  7. Critical dimension control for prevention of wafer-to-wafer and module-to-module difference

    Science.gov (United States)

    Deguchi, Masatoshi; Tanaka, Kouichirou; Nagatani, Naohiko; Miyata, Yuichiro; Yamashita, Mitsuo; Minami, Yoshiaki; Matsuyama, Yuji

    2004-05-01

    In recent years, the worldwide semiconductor market has changed drastically, and it is expected that the digital device market will continue to expand towards general consumer electronics and away from the personal computers that have been the core of the market. To accommodate this shift, the new devices will be diversified with improved productivity, higher process yield, and higher precision. Clean Track (LITHIUS) design also has been changed drastically to maintain equal productivity with new high throughput exposure equipment. Design changes include increasing the number of processing chambers by stacking reduced size modules in order to meet high throughput and small footprint requirements. However, this design change concept raises concerns about increased wafer-to-wafer difference (WtW) and module-to-module different (MtM). These variations can result in lower process yield and have a negative effect on design rule shrinkage. The primary causes of WtW difference and MtM difference stem from minute module hardware variations, module height differences, and module parameter adjustment differences during the installation of the tool. Previous Clean Track development focused mainly on reduction of module hardware difference as an approach to reduce WtW variation. However, to further improve lot level uniformity, it is necessary to reduce module height difference factors within the system and module adjustment disparities such as plate temperature calibrations. Highly temperature sensitive ArF processes have necessitated precise manual PEB temperature adjustments. These calibrations are labor intensive and require many field hours to ensure optimal CD uniformity. Therefore, an auto temperature measurement and adjustment tool is developed to eliminate the human error due to manual adjustment and minimize adjustment time. In order to meet demands for design rules shrinkage and increased process uniformity we minimized the WtW and MtM difference by using thermal

  8. Wafer-scale fabrication of polymer distributed feedback lasers

    DEFF Research Database (Denmark)

    Christiansen, Mads Brøkner; Schøler, Mikkel; Balslev, Søren

    2006-01-01

    The authors demonstrate wafer-scale, parallel process fabrication of distributed feedback (DFB) polymer dye lasers by two different nanoimprint techniques: By thermal nanoimprint lithography (TNIL) in polymethyl methacrylate and by combined nanoimprint and photolithography (CNP) in SU-8. In both...... techniques, a thin film of polymer, doped with rhodamine-6G laser dye, is spin coated onto a Borofloat glass buffer substrate and shaped into a planar waveguide slab with first order DFB surface corrugations forming the laser resonator. When optically pumped at 532 nm, lasing is obtained in the wavelength...... range between 576 and 607 nm, determined by the grating period. The results, where 13 laser devices are defined across a 10 cm diameter wafer substrate, demonstrate the feasibility of NIL and CNP for parallel wafer-scale fabrication of advanced nanostructured active optical polymer components...

  9. Uniformity across 200 mm silicon wafers printed by nanoimprint lithography

    International Nuclear Information System (INIS)

    Gourgon, C; Perret, C; Tallal, J; Lazzarino, F; Landis, S; Joubert, O; Pelzer, R

    2005-01-01

    Uniformity of the printing process is one of the key parameters of nanoimprint lithography. This technique has to be extended to large size wafers to be useful for several industrial applications, and the uniformity of micro and nanostructures has to be guaranteed on large surfaces. This paper presents results of printing on 200 mm diameter wafers. The residual thickness uniformity after printing is demonstrated at the wafer scale in large patterns (100 μm), in smaller lines of 250 nm and in sub-100 nm features. We show that a mould deformation occurs during the printing process, and that this deformation is needed to guarantee printing uniformity. However, the mould deformation is also responsible for the potential degradation of the patterns

  10. Optical evaluation of ingot fixity in semiconductor wafer slicing

    Science.gov (United States)

    Ng, T. W.; Nallathamby, R.

    2004-11-01

    The fixity of an ingot may greatly affect the quality of wafers produced during a wire saw process and improved mechanical clamping is a means for improving ingot fixity. Here, an optical technique that is based on laser beam deflection is described. The technique was demonstrated on ingot assemblies subjected to impulse loads within a prescribed range using an original and improved clamping system. The technique revealed that the ingot assembly had lower degrees of mean displacement and standard displacement deviation under the improved clamping system. The data on warp obtained from the actual production of wafers corroborates this finding. The technique described is an effective method of quantitatively evaluating the fixity of ingots in a wafer wire saw process.

  11. [Endoscopic full-thickness resection].

    Science.gov (United States)

    Meier, B; Schmidt, A; Caca, K

    2016-08-01

    Conventional endoscopic resection techniques such as endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) are powerful tools for the treatment of gastrointestinal (GI) neoplasms. However, those techniques are limited to the superficial layers of the GI wall (mucosa and submucosa). Lesions without lifting sign (usually arising from deeper layers) or lesions in difficult anatomic positions (appendix, diverticulum) are difficult - if not impossible - to resect using conventional techniques, due to the increased risk of complications. For larger lesions (>2 cm), ESD appears to be superior to the conventional techniques because of the en bloc resection, but the procedure is technically challenging, time consuming, and associated with complications even in experienced hands. Since the development of the over-the-scope clips (OTSC), complications like bleeding or perforation can be endoscopically better managed. In recent years, different endoscopic full-thickness resection techniques came to the focus of interventional endoscopy. Since September 2014, the full-thickness resection device (FTRD) has the CE marking in Europe for full-thickness resection in the lower GI tract. Technically the device is based on the OTSC system and combines OTSC application and snare polypectomy in one step. This study shows all full-thickness resection techniques currently available, but clearly focuses on the experience with the FTRD in the lower GI tract.

  12. Wafer-Level Vacuum Packaging of Smart Sensors

    OpenAIRE

    Hilton, Allan; Temple, Dorota S.

    2016-01-01

    The reach and impact of the Internet of Things will depend on the availability of low-cost, smart sensors—“low cost” for ubiquitous presence, and “smart” for connectivity and autonomy. By using wafer-level processes not only for the smart sensor fabrication and integration, but also for packaging, we can further greatly reduce the cost of sensor components and systems as well as further decrease their size and weight. This paper reviews the state-of-the-art in the wafer-level vacuum packaging...

  13. Endoscopic resection of subepithelial tumors.

    Science.gov (United States)

    Schmidt, Arthur; Bauder, Markus; Riecken, Bettina; Caca, Karel

    2014-12-16

    Management of subepithelial tumors (SETs) remains challenging. Endoscopic ultrasound (EUS) has improved differential diagnosis of these tumors but a definitive diagnosis on EUS findings alone can be achieved in the minority of cases. Complete endoscopic resection may provide a reasonable approach for tissue acquisition and may also be therapeutic in case of malignant lesions. Small SET restricted to the submucosa can be removed with established basic resection techniques. However, resection of SET arising from deeper layers of the gastrointestinal wall requires advanced endoscopic methods and harbours the risk of perforation. Innovative techniques such as submucosal tunneling and full thickness resection have expanded the frontiers of endoscopic therapy in the past years. This review will give an overview about endoscopic resection techniques of SET with a focus on novel methods.

  14. [Laparoscopic liver resection: lessons learned after 132 resections].

    Science.gov (United States)

    Robles Campos, Ricardo; Marín Hernández, Caridad; Lopez-Conesa, Asunción; Olivares Ripoll, Vicente; Paredes Quiles, Miriam; Parrilla Paricio, Pascual

    2013-10-01

    After 20 years of experience in laparoscopic liver surgery there is still no clear definition of the best approach (totally laparoscopic [TLS] or hand-assisted [HAS]), the indications for surgery, position, instrumentation, immediate and long-term postoperative results, etc. To report our experience in laparoscopic liver resections (LLRs). Over a period of 10 years we performed 132 LLRs in 129 patients: 112 malignant tumours (90 hepatic metastases; 22 primary malignant tumours) and 20 benign lesions (18 benign tumours; 2 hydatid cysts). Twenty-eight cases received TLS and 104 had HAS. 6 right hepatectomies (2 as the second stage of a two-stage liver resection); 6 left hepatectomies; 9 resections of 3 segments; 42 resections of 2 segments; 64 resections of one segment; and 5 cases of local resections. There was no perioperative mortality, and morbidity was 3%. With TLS the resection was completed in 23/28 cases, whereas with HAS it was completed in all 104 cases. Transfusion: 4,5%; operating time: 150min; and mean length of stay: 3,5 days. The 1-, 3- and 5-year survival rates for the primary malignant tumours were 100, 86 and 62%, and for colorectal metastases 92, 82 and 52%, respectively. LLR via both TLS and HAS in selected cases are similar to the results of open surgery (similar 5-year morbidity, mortality and survival rates) but with the advantages of minimally invasive surgery. Copyright © 2012 AEC. Published by Elsevier Espana. All rights reserved.

  15. Friction mechanisms of silicon wafer and silicon wafer coated with diamond-like carbon film and two monolayers

    International Nuclear Information System (INIS)

    Singh, R. Arvind; Yoon, Eui Sung; Han, Hung Gu; Kong, Ho Sung

    2006-01-01

    The friction behaviour of Si-wafer, Diamond-Like Carbon (DLC) and two Self-Assembled Monolayers(SAMs) namely DiMethylDiChlorosilane (DMDC) and DiPhenyl-DiChlorosilane (DPDC) coated on Si-wafer was studied under loading conditions in milli-Newton (mN) range. Experiments were performed using a ball-on-flat type reciprocating micro-tribo tester. Glass balls with various radii 0.25 mm, 0.5 mm and 1 mm were used. The applied normal load was in the range of 1.5 mN to 4.8 mN. Results showed that the friction increased with the applied normal load in the case of all the test materials. It was also observed that friction was affected by the ball size. Friction increased with the increase in the ball size in the case of Si-wafer. The SAMs also showed a similar trend, but had lower values of friction than those of Si-wafer. Interestingly, for DLC it was observed that friction decreased with the increase in the ball size. This distinct difference in the behavior of friction in DLC was attributed to the difference in the operating mechanism. It was observed that Si-wafer and DLC exhibited wear, whereas wear was absent in the SAMs. Observations showed that solid-solid adhesion was dominant in Si-wafer, while plowing in DLC. The wear in these two materials significantly influenced their friction. In the case of SAMs their friction behaviour was largely influenced by the nature of their molecular chains

  16. Perioperative chemotherapy and hepatic resection for resectable colorectal liver metastases

    Science.gov (United States)

    Sakamoto, Yasuo; Hayashi, Hiromitsu; Baba, Hideo

    2015-01-01

    The role of perioperative chemotherapy in the management of initially resectable colorectal liver metastases (CRLM) is still unclear. The EPOC trial [the European Organization for Research and Treatment of Cancer (EORTC) 40983] is an important study that declares perioperative chemotherapy as the standard of care for patients with resectable CRLM, and the strategy is widely accepted in western countries. Compared with surgery alone, perioperative FOLFOX therapy significantly increased progression-free survival (PFS) in eligible patients or those with resected CRLM. Overall survival (OS) data from the EPOC trial were recently published in The Lancet Oncology, 2013. Here, we discussed the findings and recommendations from the EORTC 40983 trial. PMID:25713806

  17. Fusion bonding of Si wafers investigated by x ray diffraction

    DEFF Research Database (Denmark)

    Weichel, Steen; Grey, Francois; Rasmussen, Kurt

    2000-01-01

    The interface structure of bonded Si(001) wafers with twist angle 6.5 degrees is studied as a function of annealing temperature. An ordered structure is observed in x-ray diffraction by monitoring a satellite reflection due to the periodic modulation near the interface, which results from...

  18. Influence of the wafer biasing frequency upon etching of polymide

    International Nuclear Information System (INIS)

    Sauve, G.; Arnal, Y.; Grenier, R.; Moisan, M.

    1989-01-01

    In the commonly used RF capacitive discharge, the biasing voltage appearing on the wafer results from the discharge operating conditions and cannot be set independently, for example, from the plasma density. In electrodeless high frequency (HF) produced plasmas, independent biasing of the wafer is possible. In particular, one can set the biasing voltage at a frequency different from that of the HF field sustaining the plasma. In that respect, it has been shown that biasing the wafer at 13.56 MHz in a 2.45 GHz microwave sustained plasma can lead to a substantial increase in the etch rate. The influence on etch rate when biasing the wafer at frequencies f that are below and above the ion plasma frequency p i . This experiment is performed in a reactor that was recently developed for the study of the influence of the plasma stimulating frequency (13.56-2450 MHz) upon the etching of polyimide. In such a device, the plasma is sustained by a surface wave. In the present work, the authors are concerned with the etch rate of Ciba-Geigy XU-287 polyimide in an O 2 -CF 4 discharge sustained at a fixed frequency of 200 MHz

  19. Wafer-Scale Aluminum Nanoplasmonic Resonators with Optimized Metal Deposition

    Science.gov (United States)

    2016-01-04

    plasmonics. Unlike plasmonic devices based on coinage metals , such as gold and silver , which are effectively banned from silicon semiconductor fabrication...necessarily represent the view of the United States Government. Wafer-scale Aluminum Nanoplasmonic Resonators with Optimized Metal Deposition...method of aluminum deposition. Three-layer metal -dielectric- metal nanopillar arrays were fabricated in a complementary metal -oxide semiconductor (CMOS

  20. 3D Align overlay verification using glass wafers

    NARCIS (Netherlands)

    Smeets, E.M.J.; Bijnen, F.C.G.; Slabbekoorn, J.; Van Zeijl, H.W.

    2004-01-01

    In the MEMS world, increasing attention is being given to 3D devices requiring dual-sided processing. This requires lithography tools that are able to align a wafer to both its back side as front side. Overlay describes how well front and back side layers are positioned with respect to each other.

  1. Wafer scale coating of polymer cantilever fabricated by nanoimprint lithography

    DEFF Research Database (Denmark)

    Greve, Anders; Dohn, Søren; Keller, Stephan Urs

    2010-01-01

    Microcantilevers can be fabricated in TOPAS by nanoimprint lithography, with the dimensions of 500 ¿m length 4.5 ¿m thickness and 100 ¿m width. By using a plasma polymerization technique it is possible to selectively functionalize individually cantilevers with a polymer coating, on wafer scale...

  2. Scatterometry on pelliclized masks: an option for wafer fabs

    Science.gov (United States)

    Gallagher, Emily; Benson, Craig; Higuchi, Masaru; Okumoto, Yasuhiro; Kwon, Michael; Yedur, Sanjay; Li, Shifang; Lee, Sangbong; Tabet, Milad

    2007-03-01

    Optical scatterometry-based metrology is now widely used in wafer fabs for lithography, etch, and CMP applications. This acceptance of a new metrology method occurred despite the abundance of wellestablished CD-SEM and AFM methods. It was driven by the desire to make measurements faster and with a lower cost of ownership. Over the last year, scatterometry has also been introduced in advanced mask shops for mask measurements. Binary and phase shift masks have been successfully measured at all desired points during photomask production before the pellicle is mounted. There is a significant benefit to measuring masks with the pellicle in place. From the wafer fab's perspective, through-pellicle metrology would verify mask effects on the same features that are characterized on wafer. On-site mask verification would enable quality control and trouble-shooting without returning the mask to a mask house. Another potential application is monitoring changes to mask films once the mask has been delivered to the fab (haze, oxide growth, etc.). Similar opportunities apply to the mask metrologist receiving line returns from a wafer fab. The ability to make line-return measurements without risking defect introduction is clearly attractive. This paper will evaluate the feasibility of collecting scatterometry data on pelliclized masks. We explore the effects of several different pellicle types on scatterometry measurements made with broadband light in the range of 320-780 nm. The complexity introduced by the pellicles' optical behavior will be studied.

  3. Sacrificial wafer bonding for planarization after very deep etching

    NARCIS (Netherlands)

    Spiering, V.L.; Spiering, Vincent L.; Berenschot, Johan W.; Elwenspoek, Michael Curt; Fluitman, J.H.J.

    A new technique is presented that provides planarization after a very deep etching step in silicon. This offers the possibility for as well resist spinning and layer patterning as realization of bridges or cantilevers across deep holes or grooves. The sacrificial wafer bonding technique contains a

  4. Wafer scale integration of catalyst dots into nonplanar microsystems

    DEFF Research Database (Denmark)

    Gjerde, Kjetil; Kjelstrup-Hansen, Jakob; Gammelgaard, Lauge

    2007-01-01

    diameter nickel catalyst dots on a wafer scale are presented and compared. Three of the methods are based on a p-Si layer utilized as an in situ mask, an encapsulating layer, and a sacrificial window mask, respectively. All methods enable precise positioning of nickel catalyst dots at the end...

  5. Method for reuse of wafers for growth of vertically-aligned wire arrays

    Science.gov (United States)

    Spurgeon, Joshua M; Plass, Katherine E; Lewis, Nathan S; Atwater, Harry A

    2013-06-04

    Reusing a Si wafer for the formation of wire arrays by transferring the wire arrays to a polymer matrix, reusing a patterned oxide for several array growths, and finally polishing and reoxidizing the wafer surface and reapplying the patterned oxide.

  6. Trace analysis for 300 MM wafers and processes with TXRF

    International Nuclear Information System (INIS)

    Nutsch, A.; Erdmann, V.; Zielonka, G.; Pfitzner, L.; Ryssel, H.

    2000-01-01

    Efficient fabrication of semiconductor devices is combined with an increasing size of silicon wafers. The contamination level of processes, media, and equipment has to decrease continuously. A new test laboratory for 300 mm was installed in view of the above mentioned aspects. Aside of numerous processing tools this platform consist electrical test methods, particle detection, vapor phase decomposition (VPD) preparation, and TXRF. The equipment is installed in a cleanroom. It is common to perform process or equipment control, development, evaluation and qualification with monitor wafers. The evaluation and the qualification of 300 mm equipment require direct TXRF on 300 mm wafers. A new TXRF setup was installed due to the wafer size of 300 mm. The 300 mm TXRF is equipped with tungsten and molybdenum anode. This combination allows a sensitive detection of elements with fluorescence energy below 10 keV for tungsten excitation. The molybdenum excitation enables the detection of a wide variety of elements. The detection sensitivity for the tungsten anode excited samples is ten times higher than for molybdenum anode measured samples. The system is calibrated with 1 ng Ni. This calibration shows a stability within 5 % when monitored to control system stability. Decreasing the amount of Ni linear results in a linear decrease of the measured Ni signal. This result is verified for a range of elements by multielement samples. New designs demand new processes and materials, e.g. ferroelectric layers and copper. The trace analysis of many of these materials is supported by the higher excitation energy of the molybdenum anode. Reclaim and recycling of 300 mm wafers demand for an accurate contamination control of the processes to avoid cross contamination. Polishing or etching result in modified surfaces. TXRF as a non-destructive test method allows the simultaneously detection of a variety of elements on differing surfaces in view of contamination control and process

  7. Wafer based mask characterization for double patterning lithography

    Science.gov (United States)

    de Kruif, Robert; Bubke, Karsten; Janssen, Gert-Jan; van der Heijden, Eddy; Fochler, Jörg; Dusa, Mircea; Peters, Jan Hendrik; de Haas, Paul; Connolly, Brid

    2008-04-01

    Double Patterning Technology (DPT) is considered the most acceptable solution for 32nm node lithography. Apart from the obvious drawbacks of additional exposure and processing steps and therefore reduced throughput, DPT possesses a number of additional technical challenges. This relates to exposure tool capability, the actual applied process in the wafer fab but also to mask performance. This paper will focus on the latter. We will report on the performance of a two-reticle set based on a design developed to study the impact of mask global and local placement errors on a DPT dual line process. For 32 nm node lithography using DPT a reticle to reticle overlay contribution target of data resulting from the earlier mentioned reticle set. The reticles contain a 13x19 array of modules comprising various standard overlay features such as ASML overlay gratings and bar-in-bar overlay targets. Furthermore the modules contain split 40nm half pitch DPT features. The reticles have been exposed on an ASML XT:1700i on several wafers in multiple fields. Reticle to reticle overlay contribution has been studied in resist (double exposure) and using the IMEC dual line process (DPT). We will show that the reticle to reticle overlay contribution on the wafer is smaller than 1.5nm (1x). We will compare the wafer data with the reticle data, study the correlation and show that reticle to reticle overlay contribution based single mask registration measurements can be used to qualify the reticle to reticle overlay contribution on wafer.

  8. An electron-multiplying 'Micromegas' grid made in silicon wafer post-processing technology

    NARCIS (Netherlands)

    Chefdeville, M.; Chefdeville, M.A.; Colas, P.; Giomataris, Y.; van der Graaf, H.; Heijne, E.H.M.; van der Putten, S.; Salm, Cora; Schmitz, Jurriaan; Smits, Sander M.; Timmermans, J.; Visschers, J.L.

    A technology for manufacturing an aluminium grid onto a silicon wafer has been developed. The grid is fixed parallel and precisely to the wafer (anode) surface at a distance of 50 μm by means of insulating pillars. When some 400 V are applied between the grid and (anode) wafer, gas multiplication

  9. An electron-multiplying 'Micromegas' grid made in silicon wafer post-processing technology

    NARCIS (Netherlands)

    Chefdeville, M.; Chefdeville, M.A.; Colas, P.; Giomataris, Y.; van der Graaf, H.; Heijne, E.H.M.; van der Putten, S.; Salm, Cora; Schmitz, Jurriaan; Smits, Sander M.; Timmermans, J.; Visschers, J.L.

    2005-01-01

    A technology for manufacturing an aluminium grid onto a silicon wafer has been developed. The grid is fixed parallel and precisely to the wafer (anode) surface at a distance of 50 μm by means of insulating pillars. When some 400 V are applied between the grid and (anode) wafer, gas multiplication

  10. An electron-multiplying ''Micromegas'' grid made in silicon wafer post-processing technology

    NARCIS (Netherlands)

    Chefdeville, M.A.; Colas, P.; Giomataris, Y.; van der Graaf, H.; Heijne, E.H.M.; van der Putten, S.; Salm, Cora; Schmitz, Jurriaan; Smits, Sander M.; Timmermans, J.; Timmermans, J.; Visschers, J.L.

    2005-01-01

    A technology for manufacturing an aluminium grid onto a silicon wafer has been developed. The grid is fixed parallel and precisely to the wafer (anode) surface at a distance of 50 mm by means of insulating pillars. When some 400V are applied between the grid and (anode) wafer, gas multiplication

  11. Procedure for the ion implantation of semiconductor wafers coated with insulating layers

    International Nuclear Information System (INIS)

    Baumann, K.; Tunnat, K.

    1987-01-01

    This invention is directed to the ion implantation of semiconductor wafers coated with insulating layers. The aim is to limit the spark puncturing by the ion beam due to electric charge and thus to protect the component structures. A conductive contact between semiconductor wafer and wafer carrier of the ion implantation facility is established by the partial removal of the insulating layer. 4 figs

  12. Fabrication of Ge-on-insulator wafers by Smart-CutTM with thermal management for undamaged donor Ge wafers

    Science.gov (United States)

    Kim, Munho; Cho, Sang June; Jayeshbhai Dave, Yash; Mi, Hongyi; Mikael, Solomon; Seo, Jung-Hun; Yoon, Jung U.; Ma, Zhenqiang

    2018-01-01

    Newly engineered substrates consisting of semiconductor-on-insulator are gaining much attention as starting materials for the subsequent transfer of semiconductor nanomembranes via selective etching of the insulating layer. Germanium-on-insulator (GeOI) substrates are critically important because of the versatile applications of Ge nanomembranes (Ge NMs) toward electronic and optoelectronic devices. Among various fabrication techniques, the Smart-CutTM technique is more attractive than other methods because a high temperature annealing process can be avoided. Another advantage of Smart-CutTM is the reusability of the donor Ge wafer. However, it is very difficult to realize an undamaged Ge wafer because there exists a large mismatch in the coefficient of thermal expansion among the layers. Although an undamaged donor Ge wafer is a prerequisite for its reuse, research related to this issue has not yet been reported. Here we report the fabrication of 4-inch GeOI substrates using the direct wafer bonding and Smart-CutTM process with a low thermal budget. In addition, a thermo-mechanical simulation of GeOI was performed by COMSOL to analyze induced thermal stress in each layer of GeOI. Crack-free donor Ge wafers were obtained by annealing at 250 °C for 10 h. Raman spectroscopy and x-ray diffraction (XRD) indicated similarly favorable crystalline quality of the Ge layer in GeOI compared to that of bulk Ge. In addition, Ge p-n diodes using transferred Ge NM indicate a clear rectifying behavior with an on and off current ratio of 500 at ±1 V. This demonstration offers great promise for high performance transferrable Ge NM-based device applications.

  13. Wafer-level packaging with compression-controlled seal ring bonding

    Science.gov (United States)

    Farino, Anthony J

    2013-11-05

    A device may be provided in a sealed package by aligning a seal ring provided on a first surface of a first semiconductor wafer in opposing relationship with a seal ring that is provided on a second surface of a second semiconductor wafer and surrounds a portion of the second wafer that contains the device. Forcible movement of the first and second wafer surfaces toward one another compresses the first and second seal rings against one another. A physical barrier against the movement, other than the first and second seal rings, is provided between the first and second wafer surfaces.

  14. Silicon-to-silicon wafer bonding using evaporated glass

    DEFF Research Database (Denmark)

    Weichel, Steen; Reus, Roger De; Lindahl, M.

    1998-01-01

    of silicon/glass structures in air around 340 degrees C for 15 min leads to stress-free structures. Bonded wafer pairs, however, show no reduction in stress and always exhibit compressive stress. The bond yield is larger than 95% for bonding temperatures around 350 degrees C and is above 80% for bonding......Anodic bending of silicon to silicon 4-in. wafers using an electron-beam evaporated glass (Schott 8329) was performed successfully in air at temperatures ranging from 200 degrees C to 450 degrees C. The composition of the deposited glass is enriched in sodium as compared to the target material....... The roughness of the as-deposited films was below 5 nm and was found to be unchanged by annealing at 500 degrees C for 1 h in air. No change in the macroscopic edge profiles of the glass film was found as a function of annealing; however, small extrusions appear when annealing above 450 degrees C. Annealing...

  15. Ion beam studies of hydrogen implanted Si wafers

    International Nuclear Information System (INIS)

    Nurmela, A.; Henttinen, K.; Suni, T.; Tolkki, A.; Suni, I.

    2004-01-01

    We have studied silicon-on-insulator (SOI) materials with two different ion beam analysis methods. The SOI samples were implanted with boron and hydrogen ions. After implantation the wafers were annealed, and some of them were bonded to thermally oxidized silicon wafers. The damage in silicon single crystal due to ion implantations has been studied by Rutherford Backscattering in the channeling mode (RBS/C). The content of the ion-implanted hydrogen has been studied by elastic recoil detection analysis (ERDA) method. The strength of the implanted region after thermal annealings were measured with the crack opening method. The boron implantation before hydrogen implantation resulted to shallower implantation depth and lower splitting temperature than in samples implanted with hydrogen only. The boron implantation after hydrogen implantation did not influence the splitting temperature and RBS spectra showed that B implantation drove the H deeper to the sample

  16. Denuded zone in Czochralski silicon wafer with high carbon content

    International Nuclear Information System (INIS)

    Chen Jiahe; Yang Deren; Ma Xiangyang; Que Duanlin

    2006-01-01

    The thermal stability of the denuded zone (DZ) created by high-low-high-temperature annealing in high carbon content (H[C]) and low carbon content (L[C]) Czochralski silicon (Cz-Si) has been investigated in a subsequent ramping and isothermal 1050 deg. C annealing. The tiny oxygen precipitates which might occur in the DZ were checked. It was found in the L[C] Cz-Si that the DZ shrank and the density of bulk micro-defects (BMDs) reduced with the increase of time spent at 1050 deg. C. Also, the DZs above 15 μm of thickness present in the H[C] Cz-Si wafers continuously and the density and total volume of BMDs first decreased then increased and finally decreased again during the treatments. Moreover, tiny oxygen precipitates were hardly generated inside the DZs, indicating that H[C] Cz-Si wafers could support the fabrication of integrated circuits

  17. Denuded zone in Czochralski silicon wafer with high carbon content

    Science.gov (United States)

    Chen, Jiahe; Yang, Deren; Ma, Xiangyang; Que, Duanlin

    2006-12-01

    The thermal stability of the denuded zone (DZ) created by high-low-high-temperature annealing in high carbon content (H[C]) and low carbon content (L[C]) Czochralski silicon (Cz-Si) has been investigated in a subsequent ramping and isothermal 1050 °C annealing. The tiny oxygen precipitates which might occur in the DZ were checked. It was found in the L[C] Cz-Si that the DZ shrank and the density of bulk micro-defects (BMDs) reduced with the increase of time spent at 1050 °C. Also, the DZs above 15 µm of thickness present in the H[C] Cz-Si wafers continuously and the density and total volume of BMDs first decreased then increased and finally decreased again during the treatments. Moreover, tiny oxygen precipitates were hardly generated inside the DZs, indicating that H[C] Cz-Si wafers could support the fabrication of integrated circuits.

  18. Chemical method for producing smooth surfaces on silicon wafers

    Science.gov (United States)

    Yu, Conrad

    2003-01-01

    An improved method for producing optically smooth surfaces in silicon wafers during wet chemical etching involves a pre-treatment rinse of the wafers before etching and a post-etching rinse. The pre-treatment with an organic solvent provides a well-wetted surface that ensures uniform mass transfer during etching, which results in optically smooth surfaces. The post-etching treatment with an acetic acid solution stops the etching instantly, preventing any uneven etching that leads to surface roughness. This method can be used to etch silicon surfaces to a depth of 200 .mu.m or more, while the finished surfaces have a surface roughness of only 15-50 .ANG. (RMS).

  19. Cost of Czochralski wafers as a function of diameter

    Science.gov (United States)

    Leipold, M. H.; Radics, C.; Kachare, A.

    1980-02-01

    The impact of diameter in the range of 10 to 15 cm on the cost of wafers sliced from Czochralski ingots was analyzed. Increasing silicon waste and decreasing ingot cost with increasing ingot size were estimated along with projected costs. Results indicate a small but continuous decrease in sheet cost with increasing ingot size in this size range. Sheet costs including silicon are projected to be $50 to $60/sq m (1980 $) depending upon technique used.

  20. Optical coating uniformity of 200mm (8") diameter precut wafers

    Science.gov (United States)

    Burt, Travis C.; Fisher, Mark; Brown, Dean; Troiani, David

    2017-02-01

    Automated spectroscopic profiling (mapping) of a 200 mm diameter near infrared high reflector (centered at 1064 nm) are presented. Spatial resolution at 5 mm or less was achieved using a 5 mm × 1.5 mm monochromatic beam. Reflection changes of 1.0% across the wafer diameter were observed under s-polarized and p- polarized conditions. Redundancy was established for each chord by re-measuring the center of the wafer and reproducibility of approximately used to measure the reflectance and transmittance of a sample across a range of angles (θi) at near normal angles of incidence (AOI). A recent development by Agilent Technologies, the Cary 7000 Universal Measurement Spectrophotometer (UMS) combines both reflection and transmission measurements from the same patch of a sample's surface in a single automated platform for angles of incidence in the range 5°use of MPS on the Cary 7000 UMS with rotational (Φ) and vertical (z) sample positioning control. MPS(θi,Φ,z) provides for automated unattended multi-angle R/T analysis of at 200 mm diameter samples with the goal to provide better spectroscopic measurement feedback into large wafer manufacturing to ensure yields are maximized, product quality is better controlled and waste is reduced before further down-stream processing.

  1. Metal adsorbent for alkaline etching aqua solutions of Si wafer

    International Nuclear Information System (INIS)

    Tamada, Masao; Ueki, Yuji; Seko, Noriaki; Takeda, Toshihide; Kawano, Shin-ichi

    2012-01-01

    High performance adsorbent is expected to be synthesized for the removal of Ni and Cu ions from strong alkaline solution used in the surface etching process of Si wafer. Fibrous adsorbent was synthesized by radiation-induce emulsion graft polymerization onto polyethylene nonwoven fabric and subsequent amination. The reaction condition was optimized using 30 L reaction vessel and nonwoven fabric, 0.3 m width and 18 m long. The resulting fibrous adsorbent was evaluated by 48 wt% NaOH and KOH contaminated with Ni and Cu ions, respectively. The concentration levels of Ni and Cu ions was reduced to less than 1 μg/kg (ppb) at the flow rate of 10 h −1 in space velocity. The life of adsorbent was 30 times higher than that of the commercialized resin. This novel adsorbent was commercialized as METOLATE ® since the ability of adsorption is remarkably higher than that of commercial resin used practically in Si wafer processing. - Highlights: ► Adsorbent was synthesized by radiation-induced emulsion graft polymerization. ► Degree of grafting reached 120% at the pre-irradiation of 50 kGy. ► The resulting adsorbent removed Ni and Cu ion in strong alkaline solution. ► Adsorbent was commercialized for filter of Si wafer etchant.

  2. Wafer-shape based in-plane distortion predictions using superfast 4G metrology

    Science.gov (United States)

    van Dijk, Leon; Mileham, Jeffrey; Malakhovsky, Ilja; Laidler, David; Dekkers, Harold; Van Elshocht, Sven; Anberg, Doug; Owen, David M.; van Haren, Richard

    2017-03-01

    With the latest immersion scanners performing at the sub-2 nm overlay level, the non-lithography contributors to the OnProduct-Overlay budget become more and more dominant. Examples of these contributors are etching, thin film deposition, Chemical-Mechanical Planarization and thermal anneal. These processes can introduce stress or stress changes in the thin films on top of the silicon wafers, resulting in significant wafer grid distortions. High-order wafer alignment (HOWA) is the current ASML solution for correcting wafers with a high order grid distortion introduced by non-lithographic processes, especially when these distortions vary from wafer-to-wafer. These models are currently successfully applied in high volume production at several semiconductor device manufacturers. An important precondition is that the wafer distortions remain global as the polynomial-based HOWA models become less effective for very local distortions. Wafer-shape based feed forward overlay corrections can be a possible solution to overcome this challenge. Thin film stress typically has an impact on the unclamped, free-form shape of the wafers. When an accurate relationship between the wafer shape and in-plane distortion (IPD) after clamping is established then feedforward overlay control can be enabled. In this work we assess the capability of wafer-shape based IPD predictions via a controlled experiment. The processinduced IPDs are accurately measured on the ASML TWINSCANTM system using its SMASH alignment system and the wafer shapes are measured on the Superfast 4G inspection system. In order to relate the wafer shape to the IPD we have developed a prediction model beyond the standard Stoney approximation. The match between the predicted and measured IPD is excellent ( 1-nm), indicating the feasibility of using wafer shape for feed-forward overlay control.

  3. Adhesive wafer bonding using a molded thick benzocyclobutene layer for wafer-level integration of MEMS and LSI

    Science.gov (United States)

    Makihata, M.; Tanaka, S.; Muroyama, M.; Matsuzaki, S.; Yamada, H.; Nakayama, T.; Yamaguchi, U.; Mima, K.; Nonomura, Y.; Fujiyoshi, M.; Esashi, M.

    2011-08-01

    This paper describes a wafer bonding process using a 50 µm thick benzocyclobutene (BCB) layer which has vias and metal electrodes. The vias were fabricated by molding BCB using a glass mold. During the molding, worm-like voids grew between BCB and the mold due to the shrinkage of polymerizing BCB. They were completely removed by subsequent reflowing in N2. After patterning Al on the reflowed BCB for the electrodes and via connections, bonding with a glass substrate was performed. Voidless bonding without damage in the vias and electrodes was achieved. Through the process, the control of the polymerization degree of BCB is important, and thus the polymerization degree was evaluated by Fourier transform infrared spectroscopy. The developed process is useful for the wafer-bonding-based integration of different devices, e.g. micro electro mechanical systems and large-scale integrated circuits.

  4. Adhesive wafer bonding using a molded thick benzocyclobutene layer for wafer-level integration of MEMS and LSI

    International Nuclear Information System (INIS)

    Makihata, M; Tanaka, S; Muroyama, M; Matsuzaki, S; Esashi, M; Yamada, H; Nakayama, T; Yamaguchi, U; Mima, K; Nonomura, Y; Fujiyoshi, M

    2011-01-01

    This paper describes a wafer bonding process using a 50 µm thick benzocyclobutene (BCB) layer which has vias and metal electrodes. The vias were fabricated by molding BCB using a glass mold. During the molding, worm-like voids grew between BCB and the mold due to the shrinkage of polymerizing BCB. They were completely removed by subsequent reflowing in N 2 . After patterning Al on the reflowed BCB for the electrodes and via connections, bonding with a glass substrate was performed. Voidless bonding without damage in the vias and electrodes was achieved. Through the process, the control of the polymerization degree of BCB is important, and thus the polymerization degree was evaluated by Fourier transform infrared spectroscopy. The developed process is useful for the wafer-bonding-based integration of different devices, e.g. micro electro mechanical systems and large-scale integrated circuits

  5. Identification and long term stability of DNA captured on a dental impression wafer.

    Science.gov (United States)

    Kim, Maile; Siegler, Kate; Tamariz, Jeannie; Caragine, Theresa; Fernandez, Jill; Daronch, Marcia; Moursi, Amr

    2012-01-01

    The purpose of this study was to determine the quantity and quality of DNA extracted from a dental bite impression wafer immediately after impression and after 12 months of home storage. The authors' hypothesis was that the wafer would retain sufficient DNA with appropriate genetic markers to make an identification match. Two impression wafers (Toothprints(®) brand) were administered to 100 3- to 26-year-olds. A cotton swab was used as a control. DNA from wafers stored for 12 months at home were compared to DNA collected at time 0 and compared to swabs at specific sites to determine quality and accuracy. The amount of DNA captured and recovered was analyzed using MagAttract technology and a quantitative real-time polymerase chain reaction. Capillary gel electrophoresis was performed to determine the quality of the DNA profiles obtained from the wafers vs those generated from the swabs of each subject. Average DNA concentration was: 480 pg/μL (wafer at time 0); 392 pg/μL (wafer after 12 months kept by subjects); and 1,041 pg/μL (buccal swab). Sufficient DNA for human identification was recovered from all sets of wafers, producing clear DNA profiles and accurate matches to buccal swabs. No inhibitors were found that could interfere with DNA profiling. Toothprints® impression wafers can be useful for DNA collection and child identification. After 12 months, the wafer was still usable for DNA capture and identification match.

  6. Optical pressure sensor head fabrication using ultrathin silicon wafer anodic bonding

    Science.gov (United States)

    Beggans, Michael H.; Ivanov, Dentcho I.; Fu, Steven G.; Digges, Thomas G., III; Farmer, Kenneth R.

    1999-03-01

    A technology for fabricating fiber optically interrogated pressure sensors is described. This technology is based on anodic bonding of ultra-thin silicon wafers to patterned, micro-machined glass wafers, providing low-cost fabrication of optical pressure sensor heads that operate with reproducible technical characteristics in various dynamic ranges. Pressure sensors using 10, 20 and 50 micron thick silicon wafers for membranes have been fabricated on 10 cm diameter, 500-micron thick, Pyrex glass wafers. The glass wafers have been micro-machined using ultrasonic drilling in order to form cavities, optical fiber feedthrough holes and vent holes. One of the main challenges of the manufacturing process is the handling of the ultra-thin silicon wafers. Being extremely flexible, the thin silicon wafers cannot be cleaned, oxidized, or dried in the same way as normal since wafers with a thickness of the order of 400 microns. Specific handling techniques have been developed in order to achieve reproducible cleaning and oxidation processes. The anodic bonding was performed using an Electronic Visions EV501S bonder. The wafers were heated at 420 degrees C and a voltage of 1200 volts was applied in vacuum of 10-5 Torr. The bonded wafer stack was then fixed in a wax and diced. The resulting chips have been used to fabricate operating pressure sensors.

  7. Magnetron target designs to improve wafer edge trench filling in ionized metal physical vapor deposition

    International Nuclear Information System (INIS)

    Lu Junqing; Yoon, Jae-Hong; Shin, Keesam; Park, Bong-Gyu; Yang Lin

    2006-01-01

    Severe asymmetry of the metal deposits on the trench sidewalls occurs near the wafer edge during low pressure ionized metal physical vapor deposition of Cu seed layer for microprocessor interconnects. To investigate this process and mitigate the asymmetry, an analytical view factor model based on the analogy between metal sputtering and diffuse thermal radiation was constructed. The model was validated based on the agreement between the model predictions and the reported experimental values for the asymmetric metal deposition at trench sidewalls near the wafer edge for a 200 mm wafer. This model could predict the thickness of the metal deposits across the wafer, the symmetry of the deposits on the trench sidewalls at any wafer location, and the angular distributions of the metal fluxes arriving at any wafer location. The model predictions for the 300 mm wafer indicate that as the target-to-wafer distance is shortened, the deposit thickness increases and the asymmetry decreases, however the overall uniformity decreases. Up to reasonable limits, increasing the target size and the sputtering intensity for the outer target portion significantly improves the uniformity across the wafer and the symmetry on the trench sidewalls near the wafer edge

  8. Persentase Karkas Itik Peking yang Diberi Pakan dalam Bentuk Wafer Ransum Komplit Mengandung Limbah Kopi

    Directory of Open Access Journals (Sweden)

    Muhammad Daud

    2016-04-01

    Full Text Available ABSTRAK. Penggunaan wafer ransum komplit mengandung limbah kopi pada itik peking dilakukan dengan tujuan untuk mengetahui berat akhir dan persentase karkas. Materi penelitian yang digunakan adalah itik peking umur 1 hari (DOD sebanyak 96 ekor dibagi dalam 4 perlakuan dan 3 ulangan. Ransum yang digunakan satu bulan pertama adalah ransum komersil, dan satu bulan terakhir wafer ransum komplit mengandung limbah kopi. Ransum perlakuan yang diberikan adalah: P0 = Wafer ransum komplit 0% limbah kopi (kontrol, P1 = Wafer ransum komplit 2,5% limbah kopi, P2 = Wafer ransum komplit 5% limbah kopi, dan P3 = Wafer ransum komplit 7,5% limbah kopi. Parameter yang diamati: bobot hidup, bobot karkas, bobot potongan karkas, persentase karkas, dan persentase potongan karkas. Penelitian ini menggunakan Rancangan Acak Lengkap. Data dianalisis dengan analysis of variance dan dilanjutkan dengan Uji Duncan. Hasil penelitian menunjukkan penggunaan limbah kulit kopi sebagai bahan penyusun ransum itik peking dalam bentuk wafer ransum komplit berpengaruh nyata terhadap bobot akhir. Penggunaan limbah kulit kopi 2,5% dalam ransum secara signifikan (P<0.05 meningkatkan bobot karkas dan potongan karkas. Dapat disimpulkan penggunaan limbah kulit kopi sebanyak 2,5% sebagai bahan penyusun wafer ransum komplit tidak memberi pengaruh negatif terhadap bobot badan akhir, persentase karkas dan potongan karkas itik peking.    (Carcass percentage of peking duck feed wafer complete ration containing of coffee waste  ABSTRACT. This research was conducted to study the effectiveness of wafer complete ration containing coffee waste on the final body weight and carcass percentage. The study used 96 DOD Peking duck. Completely Randomized Design (CRD consisting of 4 treatments and 3 replications. Rations used during the first month was a commercial ration, and then subsequently wafer complete ration of coffee waste given as treatments; P0 = wafer complete ration contained 0% of coffee waste

  9. Laparoscopic liver resection with radiofrequency.

    Science.gov (United States)

    Croce, E; Olmi, S; Bertolini, A; Erba, L; Magnone, S

    2003-01-01

    In this report, the feasibility, efficacy and safety of laparoscopic liver resection with radiofrequency has been evaluated in a small series of patients. From January 1993 to May 2002 we carried out 7 laparoscopic liver resections (3 men and 4 women), five of which were for benign pathology and two for metastases from colorectal cancer. In four of the above resections we used an argon coagulator; the last three were accomplished by means of a radiofrequency instrument. We had no perioperative or postoperative complications in this small series of patients. There were no deaths. Perioperative blood loss was of 120 mL (range 80-200) and the procedure took about 90 minutes (range 80-110). Hospitalization was of 4 days and pain was adequately controlled by 2 mL of Toradol twice a day. We think that the advantages of laparoscopic techniques together with the efficacy of the radiofrequency instrument in hepatic surgery will allow the diffusion of this method and its extension to safe execution of major resections.

  10. Awake craniotomy for tumor resection

    Directory of Open Access Journals (Sweden)

    Mohammadali Attari

    2013-01-01

    Full Text Available Surgical treatment of brain tumors, especially those located in the eloquent areas such as anterior temporal, frontal lobes, language, memory areas, and near the motor cortex causes high risk of eloquent impairment. Awake craniotomy displays major rule for maximum resection of the tumor with minimum functional impairment of the Central Nervous System. These case reports discuss the use of awake craniotomy during the brain surgery in Alzahra Hospital, Isfahan, Iran. A 56-year-old woman with left-sided body hypoesthesia since last 3 months and a 25-year-old with severe headache of 1 month duration were operated under craniotomy for brain tumors resection. An awake craniotomy was planned to allow maximum tumor intraoperative testing for resection and neurologic morbidity avoidance. The method of anesthesia should offer sufficient analgesia, hemodynamic stability, sedation, respiratory function, and also awake and cooperative patient for different neurological test. Airway management is the most important part of anesthesia during awake craniotomy. Tumor surgery with awake craniotomy is a safe technique that allows maximal resection of lesions in close relationship to eloquent cortex and has a low risk of neurological deficit.

  11. Science and technology of plasma activated direct wafer bonding

    Science.gov (United States)

    Roberds, Brian Edward

    This dissertation studied the kinetics of silicon direct wafer bonding with emphasis on low temperature bonding mechanisms. The project goals were to understand the topological requirements for initial bonding, develop a tensile test to measure the bond strength as a function of time and temperature and, using the kinetic information obtained, develop lower temperature methods of bonding. A reproducible surface metrology metric for bonding was best described by power spectral density derived from atomic force microscopy measurements. From the tensile strength kinetics study it was found that low annealing temperatures could be used to obtain strong bonds, but at the expense of longer annealing times. Three models were developed to describe the kinetics. A diffusion controlled model and a reaction rate controlled model were developed for the higher temperature regimes (T > 600sp°C), and an electric field assisted oxidation model was proposed for the low temperature range. An in situ oxygen plasma treatment was used to further enhance the field-controlled mechanism which resulted in dramatic increases in the low temperature bonding kinetics. Multiple internal transmission Fourier transform infrared spectroscopy (MIT-FTIR) was used to monitor species evolution at the bonded interface and a capacitance-voltage (CV) study was undertaken to investigate charge distribution and surface states resulting from plasma activation. A short, less than a minute, plasma exposure prior to contacting the wafers was found to obtain very strong bonds for hydrophobic silicon wafers at very low temperatures (100sp°C). This novel bonding method may enable new technologies involving heterogeneous material systems or bonding partially fabricated devices to become realities.

  12. Underling modification in ion beam induced Si wafers

    International Nuclear Information System (INIS)

    Hazra, S.; Chini, T.K.; Sanyal, M.K.; Grenzer, J.; Pietsch, U.

    2005-01-01

    Subsurface (amorphous-crystalline interface) structure of keV ion beam modified Si(001) wafers was studied for the first time using non-destructive technique and compared with that of the top one. Ion-beam modifications of the Si samples were done using state-of-art high-current ion implanter facility at Saha Institute of Nuclear Physics by changing energy, dose and angle of incidence of the Ar + ion beam. To bring out the underlying modification depth-resolved x-ray grazing incidence diffraction has been carried out using synchrotron radiation facility, while the structure of the top surface was studied through atomic force microscopy

  13. Automotive SOI-BCD Technology Using Bonded Wafers

    International Nuclear Information System (INIS)

    Himi, H.; Fujino, S.

    2008-01-01

    The SOI-BCD device is excelling in high temperature operation and noise immunity because the integrated elements can be electrically separated by dielectric isolation. We have promptly paid attention to this feature and have concentrated to develop SOI-BCD devices seeking to match the automotive requirement. In this paper, the feature technologies specialized for automotive SOI-BCD devices, such as buried N + layer for impurity gettering and noise shielding, LDMOS with improved ESD robustness, crystal defect-less process, and wafer direct bonding through the amorphous layer for intelligent power IC are introduced.

  14. Conoscopic interferometry of wafers for surface-acoustic wave devices

    OpenAIRE

    Äyräs, Pekka; Friberg, Ari T.; Kaivola, Matti; Salomaa, Martti M.

    1997-01-01

    We show that in interpreting the conoscopic interference fringes, one should exercise care in employing approximate expressions which fail for certain crystal cuts. In this paper, we study 64°- and 128°-rotated Y-cut and Z-cut LiNbO3 wafers. We show that the error made in using the approximate formulae for the samples is more than 25% and that one has to use exact formulae in order to attain quantitative agreement with the experimental data. Peer reviewed

  15. Addressable Inverter Matrix Tests Integrated-Circuit Wafer

    Science.gov (United States)

    Buehler, Martin G.

    1988-01-01

    Addressing elements indirectly through shift register reduces number of test probes. With aid of new technique, complex test structure on silicon wafer tested with relatively small number of test probes. Conserves silicon area by reduction of area devoted to pads. Allows thorough evaluation of test structure characteristics and of manufacturing process parameters. Test structure consists of shift register and matrix of inverter/transmission-gate cells connected to two-by-ten array of probe pads. Entire pattern contained in square area having only 1.6-millimeter sides. Shift register is conventional static CMOS device using inverters and transmission gates in master/slave D flip-flop configuration.

  16. The Wafer and Diffusion Lot Dependence of Surface Effects Resulting from Ionizing Radiation,

    Science.gov (United States)

    An investigation of the wafer and diffusion lot dependence of surface effects resulting from ionizing radiation was conducted by irradiating samples...of transistors. The transistors were selected by the wafer and diffusion lot from which they were produced. Both NPN and PNP transistors were...the diffusion lot . With the PNP’s which were not effected to the same extent as the NPN’s the dependence on the wafer or diffusion lot was not

  17. Augmented reality in bone tumour resection

    Science.gov (United States)

    Park, Y. K.; Gupta, S.; Yoon, C.; Han, I.; Kim, H-S.; Choi, H.; Hong, J.

    2017-01-01

    Objectives We evaluated the accuracy of augmented reality (AR)-based navigation assistance through simulation of bone tumours in a pig femur model. Methods We developed an AR-based navigation system for bone tumour resection, which could be used on a tablet PC. To simulate a bone tumour in the pig femur, a cortical window was made in the diaphysis and bone cement was inserted. A total of 133 pig femurs were used and tumour resection was simulated with AR-assisted resection (164 resection in 82 femurs, half by an orthropaedic oncology expert and half by an orthopaedic resident) and resection with the conventional method (82 resection in 41 femurs). In the conventional group, resection was performed after measuring the distance from the edge of the condyle to the expected resection margin with a ruler as per routine clinical practice. Results The mean error of 164 resections in 82 femurs in the AR group was 1.71 mm (0 to 6). The mean error of 82 resections in 41 femurs in the conventional resection group was 2.64 mm (0 to 11) (p Augmented reality in bone tumour resection: An experimental study. Bone Joint Res 2017;6:137–143. PMID:28258117

  18. Wafer-level testing and test during burn-in for integrated circuits

    CERN Document Server

    Bahukudumbi, Sudarshan

    2010-01-01

    Wafer-level testing refers to a critical process of subjecting integrated circuits and semiconductor devices to electrical testing while they are still in wafer form. Burn-in is a temperature/bias reliability stress test used in detecting and screening out potential early life device failures. This hands-on resource provides a comprehensive analysis of these methods, showing how wafer-level testing during burn-in (WLTBI) helps lower product cost in semiconductor manufacturing.Engineers learn how to implement the testing of integrated circuits at the wafer-level under various resource constrain

  19. Risk factors for incomplete resection and complications in endoscopic mucosal resection for lateral spreading tumors.

    Science.gov (United States)

    Kim, Hyung Hun; Kim, Joo Hoon; Park, Seun Ja; Park, Moo In; Moon, Won

    2012-07-01

    Lateral spreading tumors (LST) are relatively large flat lesions with diameters exceeding 10 mm in length. Endoscopic mucosal resection (EMR) is a commonly used technique for removing LST. We aimed to evaluate the risk factors for incomplete resection and complications of EMR for LST. Between January 2004 and December 2010, 497 patients who underwent EMR for LST were retrospectively reviewed. Risk factors for endoscopic and histopathological complete resection, complications, and clinical outcomes were investigated. Risks for incomplete resection by piecemeal resection and en bloc resection of a lesion ≥ 30 mm were higher than for en bloc resection of a lesion LST ≥ 30 mm, hospitalize patients for 12 h and note risk for incomplete resection. (iii) Following en bloc resection for LST<30 mm, hospitalize the patient for 12 h and expect complete resection. © 2012 The Authors. Digestive Endoscopy © 2012 Japan Gastroenterological Endoscopy Society.

  20. Wafer Defect Detection Using Directional Morphological Gradient Techniques

    Directory of Open Access Journals (Sweden)

    Gongyuan Qu

    2002-07-01

    Full Text Available Accurate detection and classification of wafer defects constitute an important component of the IC production process because together they can immediately improve the yield and also provide information needed for future process improvements. One class of inspection procedures involves analyzing surface images. Because of the characteristics of the design patterns and the irregular size and shape of the defects, linear processing methods, such as Fourier transform domain filtering or Sobel edge detection, are not as well suited as morphological methods for detecting these defects. In this paper, a newly developed morphological gradient technique using directional components is applied to the detection and isolation of wafer defects. The new methods are computationally efficient and do not rely on a priori knowledge of the specific design pattern to detect particles, scratches, stains, or missing pattern areas. The directional components of the morphological gradient technique allow direction specific edge suppression and reduce the noise sensitivity. Theoretical analysis and several examples are used to demonstrate the performance of the directional morphological gradient methods.

  1. Thin-film resistance thermometers on silicon wafers

    International Nuclear Information System (INIS)

    Kreider, Kenneth G; Ripple, Dean C; Kimes, William A

    2009-01-01

    We have fabricated Pt thin-film resistors directly sputtered on silicon substrates to evaluate their use as resistance thermal detectors (RTDs). This technique was chosen to achieve more accurate temperature measurements of large silicon wafers during semiconductor processing. High-purity (0.999 968 mass fraction) platinum was sputter deposited on silicon test coupons using titanium and zirconium bond coats. These test coupons were annealed, and four-point resistance specimens were prepared for thermal evaluation. Their response was compared with calibrated platinum–palladium thermocouples in a tube furnace. We evaluated the effects of furnace atmosphere, thin-film thickness, bond coats, annealing temperature and peak thermal excursion of the Pt thin films. Secondary ion mass spectrometry (SIMS) was performed to evaluate the effect of impurities on the thermal resistance coefficient, α. We present typical resistance versus temperature curves, hysteresis plots versus temperature and an analysis of the causes of uncertainties in the measurement of seven test coupons. We conclude that sputtered thin-film platinum resistors on silicon wafers can yield temperature measurements with uncertainties of less than 1 °C, k = 1 up to 600 °C. This is comparable to or better than commercially available techniques

  2. Penggunaan Limbah Kopi Sebagai Bahan Penyusun Ransum Itik Peking dalam Bentuk Wafer Ransum Komplit

    Directory of Open Access Journals (Sweden)

    Muhammad Daud

    2013-04-01

    Full Text Available Effect of coffee waste as component of compiler ration peking duck in the form of wafer complete ration ABSTRACT. Coffee waste is a by-product of coffee processing that potential to be used as feed stuff for peking duck. The weakness of this coffee waste, among others, is perishable, voluminous (bulky and the availability was fluctuated so the processing technology is needed to make this vegetable waste to be durable, easy to stored and to be given to livestock. To solve this problem vegetable waste could be formed as wafer. This research was conducted to study effectiveness of coffee waste as component of compiler ration peking duck in the form of wafer complete ration This experiment was run in completely randomized design which consist of 4 feed treatment and 3 replications.  Ration used was consisted of  P0 = wafer complete ration 0% coffee waste (control, P1 = wafer complete ration 2,5% coffee waste, P2 = wafer complete ration 5% coffee waste, and P3 = Wafer complete ration 7,5% coffee waste. The Variables observed were: physical characteristic (aroma, color, and wafer density and palatability of wafer complete ration. Data collected was analyzed with ANOVA and Duncan Range Test would be used if the result was significantly different. The result showed that the density of wafer complete ration coffee waste was significantly (P< 0.05 differences between of treatment. Mean density wafer complete ration equal to: P0= 0,52±0,03, P1 =0,67±0,04, P2 =0,72±0,03, and P3 = 0,76±0.05 g/cm3. Wafer complete ration coffee waste palatability was significantly (P< 0.05 differences between of treatment. It is concluded that of wafer complete ration composition 5 and 7,5% coffee waste was significantly wafer palatability and gave a highest wafer density. The ration P0 was the most palatable compare to other treatments for the experimental peking duck.

  3. Assessment of the Use of 100µm Thin Germanium Wafers for High Efficiency Space Cells

    Science.gov (United States)

    Geens, Wim; Dessein, Kristof; Kostler, Wolfgang; Meusel, Matthias; Taylor, Steve; Mijlemans, Paul; Strobl, Gerhard

    2005-05-01

    The space community has always searched for ways how to reduce the mass of satellites and one of the crucial components is the solar panel. For the latter, maximising the number of generated watts per launched kilogram is key. One approach to achieve this is to realise high efficiency III-V cells on thin, lightweight substrates. In this paper it will be shown how 4" germanium wafers with a thickness of 100μm can serve this purpose. Thinner wafers could also imply a cost advantage as more wafers per cm of ingot can be produced. In addition, the fact that these substrates are bendable facilitates the use of lightweight, flexible solar arrays, yielding a further enhancement of the number of W/kg. Also the overall cost per watt (€/W) of solar panels consisting of high- efficiency cells mounted on flexible arrays is expected to be competitive with alternative future space solar cell technologies.In a first part, the approach that consists of slicing with a reduced wire distance to thin down the wafers will be addressed, as this is the most cost-effective method. Secondly, the concept where wafer thinning is accomplished by extended surface grinding will be reviewed. For both cases, the mechanical properties of the 100μm wafers were investigated. Waviness of the wafers, which is caused during the wire-slicing process, is an important parameter to control as it becomes more pronounced as the wafer gets thinner. Also wafer bow and the in-situ wafer deformation will be shortly presented. SIMS analyses were performed to verify the occurrence of autodoping effects during GaAs deposition. For this a comparison was made between the germanium content in GaAs stacks that were grown on 100μm and on 175μm wafers.One section is devoted to ground 100μm Ge wafers that can serve as base substrate to produce 20μm Ge wafers.Finally, MOCVD growth runs were done on the thin Ge substrates by RWE Space Solar Power to test the behaviour of the substrates after thermal cycling in a

  4. [Robot-assisted pancreatic resection].

    Science.gov (United States)

    Müssle, B; Distler, M; Weitz, J; Welsch, T

    2017-06-01

    Although robot-assisted pancreatic surgery has been considered critically in the past, it is nowadays an established standard technique in some centers, for distal pancreatectomy and pancreatic head resection. Compared with the laparoscopic approach, the use of robot-assisted surgery seems to be advantageous for acquiring the skills for pancreatic, bile duct and vascular anastomoses during pancreatic head resection and total pancreatectomy. On the other hand, the use of the robot is associated with increased costs and only highly effective and professional robotic programs in centers for pancreatic surgery will achieve top surgical and oncological quality, acceptable operation times and a reduction in duration of hospital stay. Moreover, new technologies, such as intraoperative fluorescence guidance and augmented reality will define additional indications for robot-assisted pancreatic surgery.

  5. Enhanced recovery after esophageal resection.

    Science.gov (United States)

    Vorwald, Peter; Bruna Esteban, Marcos; Ortega Lucea, Sonia; Ramírez Rodríguez, Jose Manuel

    2018-03-21

    ERAS is a multimodal perioperative care program which replaces traditional practices concerning analgesia, intravenous fluids, nutrition, mobilization as well as a number of other perioperative items, whose implementation is supported by evidence-based best practices. According to the RICA guidelines published in 2015, a review of the literature and the consensus established at a multidisciplinary meeting in 2015, we present a protocol that contains the basic procedures of an ERAS pathway for resective esophageal surgery. The measures involved in this ERAS pathway are structured into 3areas: preoperative, perioperative and postoperative. The consensus document integrates all the analyzed items in a unique time chart. ERAS programs in esophageal resection surgery can reduce postoperative morbidity, mortality, hospitalization and hospital costs. Copyright © 2018 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  6. Awake craniotomy for tumor resection

    OpenAIRE

    Mohammadali Attari; Sohrab Salimi

    2013-01-01

    Surgical treatment of brain tumors, especially those located in the eloquent areas such as anterior temporal, frontal lobes, language, memory areas, and near the motor cortex causes high risk of eloquent impairment. Awake craniotomy displays major rule for maximum resection of the tumor with minimum functional impairment of the Central Nervous System. These case reports discuss the use of awake craniotomy during the brain surgery in Alzahra Hospital, Isfahan, Iran. A 56-year-old woman with le...

  7. Wafer-scale fabrication of uniform Si nanowire arrays using the Si wafer with UV/Ozone pretreatment

    International Nuclear Information System (INIS)

    Bai, Fan; Li, Meicheng; Huang, Rui; Yu, Yue; Gu, Tiansheng; Chen, Zhao; Fan, Huiyang; Jiang, Bing

    2013-01-01

    The electroless etching technique combined with the process of UV/Ozone pretreatment is presented for wafer-scale fabrication of the silicon nanowire (SiNW) arrays. The high-level uniformity of the SiNW arrays is estimated by the value below 0.2 of the relative standard deviation of the reflection spectra on the 4-in. wafer. Influence of the UV/Ozone pretreatment on the formation of SiNW arrays is investigated. It is seen that a very thin SiO 2 produced by the UV/Ozone pretreatment improves the uniform nucleation of Ag nanoparticles (NPs) on the Si surface because of the effective surface passivation. Meanwhile, the SiO 2 located among the adjacent Ag NPs can obstruct the assimilation growth of Ag NPs, facilitating the deposition of the uniform and dense Ag NPs catalysts, which induces the formation of the SiNW arrays with good uniformity and high filling ratio. Furthermore, the remarkable antireflective and hydrophobic properties are observed for the SiNW arrays which display great potential in self-cleaning antireflection applications

  8. Strategy For Yield Control And Enhancement In VLSI Wafer Manufacturing

    Science.gov (United States)

    Neilson, B.; Rickey, D.; Bane, R. P.

    1988-01-01

    In most fully utilized integrated circuit (IC) production facilities, profit is very closely linked with yield. In even the most controlled manufacturing environments, defects due to foreign material are a still major contributor to yield loss. Ideally, an IC manufacturer will have ample engineering resources to address any problem that arises. In the real world, staffing limitations require that some tasks must be left undone and potential benefits left unrealized. Therefore, it is important to prioritize problems in a manner that will give the maximum benefit to the manufacturer. When offered a smorgasbord of problems to solve, most people (engineers included) will start with what is most interesting or the most comfortable to work on. By providing a system that accurately predicts the impact of a wide variety of defect types, a rational method of prioritizing engineering effort can be made. To that effect, a program was developed to determine and rank the major yield detractors in a mixed analog/digital FET manufacturing line. The two classical methods of determining yield detractors are chip failure analysis and defect monitoring on drop in test die. Both of these methods have short comings: 1) Chip failure analysis is painstaking and very time consuming. As a result, the sample size is very small. 2) Drop in test die are usually designed for device parametric analysis rather than defect analysis. To provide enough wafer real estate to do meaningful defect analysis would render the wafer worthless for production. To avoid these problems, a defect monitor was designed that provided enough area to detect defects at the same rate or better than the NMOS product die whose yield was to be optimized. The defect monitor was comprehensive and electrically testable using such equipment as the Prometrix LM25 and other digital testers. This enabled the quick accumulation of data which could be handled statistically and mapped individually. By scaling the defect densities

  9. Present and future role of chemical mechanical polishing in wafer bonding

    NARCIS (Netherlands)

    Gui, C.; Elwenspoek, Michael Curt; Gardeniers, Johannes G.E.; Lambeck, Paul

    Almost all direct wafer bonding has been conducted between chemical-mechanically polished substrates or between thin films that were present on top of the polished substrates. Introducing chemical mechanical polishing in the wafer bonding will make a large range of materials suitable for direct

  10. Charge carrier Density Imaging / IR lifetime mapping of Si wafers by Lock-In Thermography

    NARCIS (Netherlands)

    Van der Tempel, L.

    2012-01-01

    ABSTRACT Minority carrier lifetime imaging by lock-in thermography of passivated silicon wafers for photovoltaic cells has been developed for the public Pieken in de Delta project geZONd. CONCLUSIONS Minority carrier lifetime imaging by lock-in thermography of passivatedsilicon wafers is released

  11. Synchrotron radiation total reflection x-ray fluorescence analysis; of polymer coated silicon wafers

    International Nuclear Information System (INIS)

    Brehm, L.; Kregsamer, P.; Pianetta, P.

    2000-01-01

    It is well known that total reflection x-ray fluorescence (TXRF) provides an efficient method for analyzing trace metal contamination on silicon wafer surfaces. New polymeric materials used as interlayer dielectrics in microprocessors are applied to the surface of silicon wafers by a spin-coating process. Analysis of these polymer coated wafers present a new challenge for TXRF analysis. Polymer solutions are typically analyzed for bulk metal contamination prior to application on the wafer using inductively coupled plasma mass spectrometry (ICP-MS). Questions have arisen about how to relate results of surface contamination analysis (TXRF) of a polymer coated wafer to bulk trace analysis (ICP-MS) of the polymer solutions. Experiments were done to explore this issue using synchrotron radiation (SR) TXRF. Polymer solutions were spiked with several different concentrations of metals. These solutions were applied to silicon wafers using the normal spin-coating process. The polymer coated wafers were then measured using the SR-TXRF instrument set-up at the Stanford Synchrotron Radiation Laboratory (SSRL). Several methods of quantitation were evaluated. The best results were obtained by developing calibration curves (intensity versus ppb) using the spiked polymer coated wafers as standards. Conversion of SR-TXRF surface analysis results (atoms/cm 2 ) to a volume related concentration was also investigated. (author)

  12. Measurement of Elastic Modulus of Alumina and Barium Strontium Titanate Wafers Produced by Tape Casting Method

    Science.gov (United States)

    2014-02-01

    DATES COVERED (From – To) 4. TITLE AND SUBTITLE MEASUREMENT OF ELASTIC MODULUS OF ALUMINA AND BARIUM STRONTIUM TITANATE WAFERS PRODUCED BY...configuration testing method. Samples of barium strontium titanate (BST) were made using a regular powder pressing, sintering, pelletizing, and...fabricated using thin wafers of barium strontium titanate (BST) and aluminum oxide (alumina) ceramic during launch of a system. Sandia National

  13. Comparison of silicon strip tracker module size using large sensors from 6 inch wafers

    CERN Multimedia

    Honma, Alan

    1999-01-01

    Two large silicon strip sensor made from 6 inch wafers are placed next to each other to simulate the size of a CMS outer silicon tracker module. On the left is a prototype 2 sensor CMS inner endcap silicon tracker module made from 4 inch wafers.

  14. Systematic characterization of key parameters of hermetic wafer-level Cu-Sn SLID bonding

    NARCIS (Netherlands)

    Wiel, H.J. van de; Vardøy, A.S.B.; Hayes, G.; Kouters, M.H.M.; Waal, A. van der; Erinc, M.; Lapadatu, A.; Martinsen, S.; Taklo, M.M.V.; Fischer, H.R.

    2013-01-01

    Hermetic wafer-level encapsulation of atmosphere sensitive Micro-Electric-Mechanical Systems (MEMS) devices is vital to achieve a high yield, a high performance and a long operating lifetime. An interesting and gradually more employed packaging technique is flux-less wafer-level copper-tin (Cu-Sn)

  15. Crack detection and analyses using resonance ultrasonic vibrations in full-size crystalline silicon wafers

    International Nuclear Information System (INIS)

    Belyaev, A.; Polupan, O.; Dallas, W.; Ostapenko, S.; Hess, D.; Wohlgemuth, J.

    2006-01-01

    An experimental approach for fast crack detection and length determination in full-size solar-grade crystalline silicon wafers using a resonance ultrasonic vibrations (RUV) technique is presented. The RUV method is based on excitation of the longitudinal ultrasonic vibrations in full-size wafers. Using an external piezoelectric transducer combined with a high sensitivity ultrasonic probe and computer controlled data acquisition system, real-time frequency response analysis can be accomplished. On a set of identical crystalline Si wafers with artificially introduced periphery cracks, it was demonstrated that the crack results in a frequency shift in a selected RUV peak to a lower frequency and increases the resonance peak bandwidth. Both characteristics were found to increase with the length of the crack. The frequency shift and bandwidth increase serve as reliable indicators of the crack appearance in silicon wafers and are suitable for mechanical quality control and fast wafer inspection

  16. Simulation Research on Micro Contact Based on Force in Silicon Wafer Rotation Grinding

    Science.gov (United States)

    Ren, Qinglei; Wei, Xin; Xie, Xiaozhu; Hu, Wei

    2017-10-01

    Silicon wafer rotation grinding with cup type diamond wheel is a typical ultra precision grinding process. In this paper, a simulation model based on force for micro contact between wheel micro unit and silicon wafer is established from the stable ductile grinding process. Micro contact process in grinding is simulated using the nonlinear explicit finite element analysis software LS-DYNA. The stress-strain results on silicon wafer and wheel micro unit are analyzed by finite element method. The results show that the critical displacement and load corresponding elastic to plastic - plastic to brittle exist on silicon wafer. In silicon plastic zone tangential sliding can produce plastic groove and uplift. Wear of wheel micro unit can be based on the simulation data to judge. The research provides support for wafer grinding and wheel wear mechanism.

  17. Comparison on mechanical properties of heavily phosphorus- and arsenic-doped Czochralski silicon wafers

    Science.gov (United States)

    Yuan, Kang; Sun, Yuxin; Lu, Yunhao; Liang, Xingbo; Tian, Daxi; Ma, Xiangyang; Yang, Deren

    2018-04-01

    Heavily phosphorus (P)- and arsenic (As)-doped Czochralski silicon (CZ-Si) wafers generally act as the substrates for the epitaxial silicon wafers used to fabricate power and communication devices. The mechanical properties of such two kinds of n-type heavily doped CZ silicon wafers are vital to ensure the quality of epitaxial silicon wafers and the manufacturing yields of devices. In this work, the mechanical properties including the hardness, Young's modulus, indentation fracture toughness and the resistance to dislocation motion have been comparatively investigated for heavily P- and As-doped CZ-Si wafers. It is found that heavily P-doped CZ-Si possesses somewhat higher hardness, lower Young's modulus, larger indentation fracture toughness and stronger resistance to dislocation motion than heavily As-doped CZ-Si. The mechanisms underlying this finding have been tentatively elucidated by considering the differences in the doping effects of P and As in silicon.

  18. Temperature Uniformity of Wafer on a Large-Sized Susceptor for a Nitride Vertical MOCVD Reactor

    International Nuclear Information System (INIS)

    Li Zhi-Ming; Jiang Hai-Ying; Han Yan-Bin; Li Jin-Ping; Yin Jian-Qin; Zhang Jin-Cheng

    2012-01-01

    The effect of coil location on wafer temperature is analyzed in a vertical MOCVD reactor by induction heating. It is observed that the temperature distribution in the wafer with the coils under the graphite susceptor is more uniform than that with the coils around the outside wall of the reactor. For the case of coils under the susceptor, we find that the thickness of the susceptor, the distance from the coils to the susceptor bottom and the coil turns significantly affect the temperature uniformity of the wafer. An optimization process is executed for a 3-inch susceptor with this kind of structure, resulting in a large improvement in the temperature uniformity. A further optimization demonstrates that the new susceptor structure is also suitable for either multiple wafers or large-sized wafers approaching 6 and 8 inches

  19. Wafer size effect on material removal rate in copper CMP process

    Energy Technology Data Exchange (ETDEWEB)

    Yuh, Minjong; Jang, Soocheon; Park, Inho; Jeong, Haedo [Pusan National University, Busan (Korea, Republic of)

    2017-06-15

    The semiconductor industry has employed the Chemical mechanical planarization (CMP) to enable surface topography control. Copper has been used to build interconnects because of its low-resistivity and high-electromigration. In this study, the effect of wafer size on the Material removal rate (MRR) in copper CMP process was investigated. CMP experiments were conducted using copper blanket wafers with diameter of 100, 150, 200 and 300 mm, while temperature and friction force were measured by infrared and piezoelectric sen-sors. The MRR increases with an increase in wafer size under the same process conditions. The wafer size increased the sliding distance of pad, resulting in an increase in the process temperature. This increased the process temperature, accelerating the chemical etching rate and the dynamic etch rate. The sliding distance of the pad was proportional to the square of the wafer radius; it may be used to predict CMP results and design a CMP machine.

  20. Stickers versus wafers: The value of resource in a public goods game with children

    Directory of Open Access Journals (Sweden)

    Phiética Raíssa Rodrigues da Silva

    Full Text Available Abstract We investigated how the type of resource, food (wafer or non-food (sticker, age and sex influence cooperation in children. 251 children were tested in a public goods game during eight rounds in two experimental conditions: wafer or sticker condition. Wafers were all of the same kind but stickers were varied. The results indicated that 1 older children donated more stickers than younger children, but they did not differ in relation to wafer donations; and 2 sticker donations remained high along the rounds, while wafer donations decreased. We propose that different strategies may be adopted according to the quality, particularly to the diversity of the resource used, and the cost of cooperation may be overcome when it is more advantageous to wait for a future reward.

  1. Locally-enhanced light scattering by a monocrystalline silicon wafer

    Directory of Open Access Journals (Sweden)

    Li Ma

    2018-03-01

    Full Text Available We study the optical properties of light scattering by a monocrystalline silicon wafer, by using transparent material to replicate its surface structure and illuminating a fabricated sample with a laser source. The experimental results show that the scattering field contains four spots of concentrated intensity with high local energy, and these spots are distributed at the four vertices of a square with lines of intensity linking adjacent spots. After discussing simulations of and theory about the formation of this light scattering, we conclude that the scattering field is formed by the effects of both geometrical optics and physical optics. Moreover, we calculate the central angle of the spots in the light field, and the result indicates that the locally-enhanced intensity spots have a definite scattering angle. These results may possibly provide a method for improving energy efficiency within mono-Si based solar cells.

  2. Chemical strategies for die/wafer submicron alignment and bonding.

    Energy Technology Data Exchange (ETDEWEB)

    Martin, James Ellis; Baca, Alicia I.; Chu, Dahwey; Rohwer, Lauren Elizabeth Shea

    2010-09-01

    This late-start LDRD explores chemical strategies that will enable sub-micron alignment accuracy of dies and wafers by exploiting the interfacial energies of chemical ligands. We have micropatterned commensurate features, such as 2-d arrays of micron-sized gold lines on the die to be bonded. Each gold line is functionalized with alkanethiol ligands before the die are brought into contact. The ligand interfacial energy is minimized when the lines on the die are brought into registration, due to favorable interactions between the complementary ligand tails. After registration is achieved, standard bonding techniques are used to create precision permanent bonds. We have computed the alignment forces and torque between two surfaces patterned with arrays of lines or square pads to illustrate how best to maximize the tendency to align. We also discuss complex, aperiodic patterns such as rectilinear pad assemblies, concentric circles, and spirals that point the way towards extremely precise alignment.

  3. Ambient plasma treatment of silicon wafers for surface passivation recovery

    Science.gov (United States)

    Ge, Jia; Prinz, Markus; Markert, Thomas; Aberle, Armin G.; Mueller, Thomas

    2017-08-01

    In this work, the effect of an ambient plasma treatment powered by compressed dry air on the passivation quality of silicon wafers coated with intrinsic amorphous silicon sub-oxide is investigated. While long-time storage deteriorates the effective lifetime of all samples, a short ambient plasma treatment improves their passivation qualities. By studying the influence of the plasma treatment parameters on the passivation layers, an optimized process condition was identified which even boosted the passivation quality beyond its original value obtained immediately after deposition. On the other hand, the absence of stringent requirement on gas precursors, vacuum condition and longtime processing makes the ambient plasma treatment an excellent candidate to replace conventional thermal annealing in industrial heterojunction solar cell production.

  4. Delineation of Crystalline Extended Defects on Multicrystalline Silicon Wafers

    Directory of Open Access Journals (Sweden)

    Mohamed Fathi

    2007-01-01

    Full Text Available We have selected Secco and Yang etch solutions for the crystalline defect delineation on multicrystalline silicon (mc-Si wafers. Following experimentations and optimization of Yang and Secco etching process parameters, we have successfully revealed crystalline extended defects on mc-Si surfaces. A specific delineation process with successive application of Yang and Secco agent on the same sample has proved the increased sensitivity of Secco etch to crystalline extended defects in mc-Si materials. The exploration of delineated mc-Si surfaces indicated that strong dislocation densities are localized mainly close to the grain boundaries and on the level of small grains in size (below 1 mm. Locally, we have observed the formation of several parallel dislocation lines, perpendicular to the grain boundaries. The overlapping of several dislocations lines has revealed particular forms for etched pits of dislocations.

  5. Fabrication of PIN diode detectors on thinned silicon wafers

    CERN Document Server

    Ronchin, Sabina; Dalla Betta, Gian Franco; Gregori, Paolo; Guarnieri, Vittorio; Piemonte, Claudio; Zorzi, Nicola

    2004-01-01

    Thin substrates are one of the possible choices to provide radiation hard detectors for future high-energy physics experiments. Among the advantages of thin detectors are the low full depletion voltage, even after high particle fluences, the improvement of the tracking precision and momentum resolution and the reduced material budget. In the framework of the CERN RD50 Collaboration, we have developed p-n diode detectors on membranes obtained by locally thinning the silicon substrate by means of tetra-methyl ammonium hydroxide etching from the wafer backside. Diodes of different shapes and sizes have been fabricated on 57 and 99mum thick membranes. They have been tested, showing a very low leakage current ( less than 0.4nA/cm**2) and, as expected, a very low depletion voltage ( less than 1V for the 57mum membrane). The paper describes the technological approach used for devices fabrication and reports selected results from the electrical characterization.

  6. Single Molecule Analysis of Resection Tracks.

    Science.gov (United States)

    Huertas, Pablo; Cruz-García, Andrés

    2018-01-01

    Homologous recombination is initiated by the so-called DNA end resection, the 5'-3' nucleolytic degradation of a single strand of the DNA at each side of the break. The presence of resected DNA is an obligatory step for homologous recombination. Moreover, the amount of resected DNA modulates the prevalence of different recombination pathways. In different model organisms, there are several published ways to visualize and measure with more or less detail the amount of DNA resected. In human cells, however, technical constraints hampered the study of resection at high resolution. Some information might be gathered from the study of endonuclease-created DSBs, in which the resection of breaks at known sites can be followed by PCR or ChIP. In this chapter, we describe in detail a novel assay to study DNA end resection in breaks located on unknown positions. Here, we use ionizing radiation to induce double-strand breaks, but the same approach can be used to monitor resection induced by different DNA damaging agents. By modifying the DNA-combing technique, used for high-resolution replication analyses, we can measure resection progression at the level of individual DNA fibers. Thus, we named the method Single Molecule Analysis of Resection Tracks (SMART). We use human cells in culture as a model system, but in principle the same approach would be feasible to any model organism adjusting accordingly the DNA isolation part of the protocol.

  7. Resectable pancreatic small cell carcinoma

    Directory of Open Access Journals (Sweden)

    Dana K. Andersen

    2011-03-01

    Full Text Available Primary pancreatic small cell carcinoma (SCC is rare, with just over 30 cases reported in the literature. Only 7 of these patients underwent surgical resection with a median survival of 6 months. Prognosis of SCC is therefore considered to be poor, and the role of adjuvant therapy is uncertain. Here we report two institutions’ experience with resectable pancreatic SCC. Six patients with pancreatic SCC treated at the Johns Hopkins Hospital (4 patients and the Mayo Clinic (2 patients were identified from prospectively collected pancreatic cancer databases and re-reviewed by pathology. All six patients underwent a pancreaticoduodenectomy. Clinicopathologic data were analyzed, and the literature on pancreatic SCC was reviewed. Median age at diagnosis was 50 years (range 27-60. All six tumors arose in the head of the pancreas. Median tumor size was 3 cm, and all cases had positive lymph nodes except for one patient who only had five nodes sampled. There were no perioperative deaths and three patients had at least one postoperative complication. All six patients received adjuvant therapy, five of whom were given combined modality treatment with radiation, cisplatin, and etoposide. Median survival was 20 months with a range of 9-173 months. The patient who lived for 9 months received chemotherapy only, while the patient who lived for 173 months was given chemoradiation with cisplatin and etoposide and represents the longest reported survival time from pancreatic SCC to date. Pancreatic SCC is an extremely rare form of cancer with a poor prognosis. Patients in this surgical series showed favorable survival rates when compared to prior reports of both resected and unresectable SCC. Cisplatin and etoposide appears to be the preferred chemotherapy regimen, although its efficacy remains uncertain, as does the role of combined modality treatment with radiation.

  8. PREDIKSI MASA KEDALUWARSA WAFER DENGAN ARTIFICIAL NEURAL NETWORK (ANN BERDASARKAN PARAMETER NILAI KAPASITANSI (Prediction of Wafer Shelf Life Using Artificial Neural Network Based on Capacitance Parameter

    Directory of Open Access Journals (Sweden)

    Erna Rusliana Muhamad Saleh

    2014-02-01

    Full Text Available Wafer is type of biscuit frequently found on expired condition in market, therefore prediction method should be implemented to avoid this condition. apart from the prediction of shelf-life of wafer done by laboratory test, which were time-consuming, expensive, required trained panelists, complex equipment and suitable ambience, artificial neural network (ANN based dielectric parameters was proposed in nthis study. The aim of study was to develop model to predict shelf-life employing aNN based capacitance parameter. Back propagation algorithm with trial and error was applied in variations of nodes per hidden layer, number of hidden layers, activation functions, the function of learnings and epochs. The result of study was the model was able to predict wafer shelf-life. The accuracy level was shown by low MSE value (0.01 and high coefficient correlation value (89.25%. Keywords: artificial Neural Network, shelf-life, waffer, dielectric, capacitance   ABSTRAK Wafer adalah jenis makanan kering yang sering ditemukan kedaluwarsa. Penentuan masa kedaluwarsa dengan observasi laboratorium memiliki beberapa kelemahan, diantaranya memakan waktu, panelis terlatih, suasana yang tepat, biaya dan alat uji yang kompleks. alternatif solusinya adalah penggunaan artificial Neural Network (ANN berbasiskan parameter kapasitansi. Tujuan kerja ilmiah ini adalah untuk memprediksi masa kedaluwarsa wafer menggunakan aNN berbasiskan parameter kapasitansi. algoritma pembelajaran yang digunakan adalah Backpropagation dengan trial and error variasi jumlah node per hidden layer, jumlah hidden layer, fungsi aktivasi, fungsi pembelajaran dan epoch. Hasil prediksi menunjukkan bahwa aNN hasil pelatihan yang dikombinasikan dengan parameter kapasitansi mampu memprediksi masa kedaluwarsa wafer dengan MSE terendah 0,01 dan R tertinggi 89,25%. Kata kunci: Jaringan Syaraf Tiruan, masa kedaluwarsa, wafer, dielektrik, kapasitansi

  9. Liver resection over the last decade

    DEFF Research Database (Denmark)

    Wettergren, A.; Larsen, P.N.; Rasmussen, A.

    2008-01-01

    after resection of hepatic metastases from colorectal cancer and hepatocellular carcinoma was estimated. RESULTS: 141 patients (71M/70F), median age 58 years (1-78), underwent a liver resection in the ten-year period. The number of resections increased from two in 1995 to 32 in 2004. Median hospital...... stay was 9 days (3-38). The most frequent complication was biliary leakage (7.8%), haemorrhage (2.8%) and hepatic insufficiency (2.8%). 30-days mortality was 1.4%. The actuarial 5-survival after hepatic resection for colorectal liver metastases and hepatocellular carcinoma was 39% and 42%, respectively...

  10. Innovative metal thermo-compression wafer bonding for microelectronics and MEMS devices

    Science.gov (United States)

    Rebhan, B.; Dragoi, V.

    2017-06-01

    With the continuously increasing level of integration for microelectronics and microelectromechanical systems (MEMS) devices, such as gyroscopes, accelerometers and bolometers, metal wafer bonding becomes progressively more importance. In the present work common metal wafer bonding techniques were categorized, described and compared. While devices produced with metal thermo-compression wafer bonding ensure high bonding quality and a high degree of reliability, the required bonding temperatures are very often close to the maximum complementary metal oxide semiconductor (CMOS) compatible process temperature (400-450°C). Based on a thermodynamic model of increasing the Gibbs free energy prior wafer bonding, in-situ ComBond(R) surface activation was applied to enable low-temperature Au-Au, Al-Al and Cu-Cu wafer bonding. Different aspects, such as bonding quality, dicing yield, bond strength, grain growth and elemental analysis across the initial bonding interface, were investigated. Based on these parameters successful wafer bonding was demonstrated at room temperature for Au-Au and Cu-Cu, and at 100°C for Al-Al wafer bonding.

  11. Improvement of surface roughness in silicon-on-insulator wafer fabrication using a neutral beam etching

    Science.gov (United States)

    Min, T. H.; Park, B. J.; Kang, S. K.; Gweon, G. H.; Kim, Y. Y.; Yeom, G. Y.

    2009-08-01

    Silicon-on-insulator (SOI) wafers were etched by an energetic chlorine neutral beam obtained by the low-angle forward reflection of an ion beam, and the surface roughness of the etched wafers was compared with that of the SOI wafers etched by an energetic chlorine ion beam. When the ion beam was used to etch the silicon layer of the SOI wafers, the surface roughness was not significantly changed even though the use of higher ion bombardment energy slightly decreased the surface roughness of the SOI wafer. However, when the chlorine neutral beam was used instead of the chlorine ion beam having a similar beam energy, the surface roughness of the SOI wafer was significantly improved compared with that etched by the chlorine ion beam. By etching about 150 nm silicon from the SOI wafer having a 300 nm-thick top silicon layer with the chlorine neutral beam at the energy of 500 eV, the rms surface roughness of 1.5 Å could be obtained with the etch rate of about 750 Å min-1.

  12. Electronic properties of interfaces produced by silicon wafer hydrophilic bonding

    Energy Technology Data Exchange (ETDEWEB)

    Trushin, Maxim

    2011-07-15

    The thesis presents the results of the investigations of electronic properties and defect states of dislocation networks (DNs) in silicon produced by wafers direct bonding technique. A new insight into the understanding of their very attractive properties was succeeded due to the usage of a new, recently developed silicon wafer direct bonding technique, allowing to create regular dislocation networks with predefined dislocation types and densities. Samples for the investigations were prepared by hydrophilic bonding of p-type Si (100) wafers with same small misorientation tilt angle ({proportional_to}0.5 ), but with four different twist misorientation angles Atw (being of < , 3 , 6 and 30 , respectively), thus giving rise to the different DN microstructure on every particular sample. The main experimental approach of this work was the measurements of current and capacitance of Schottky diodes prepared on the samples which contained the dislocation network at a depth that allowed one to realize all capabilities of different methods of space charge region spectroscopy (such as CV/IV, DLTS, ITS, etc.). The key tasks for the investigations were specified as the exploration of the DN-related gap states, their variations with gradually increasing twist angle Atw, investigation of the electrical field impact on the carrier emission from the dislocation-related states, as well as the establishing of the correlation between the electrical (DLTS), optical (photoluminescence PL) and structural (TEM) properties of DNs. The most important conclusions drawn from the experimental investigations and theoretical calculations can be formulated as follows: - DLTS measurements have revealed a great difference in the electronic structure of small-angle (SA) and large-angle (LA) bonded interfaces: dominating shallow level and a set of 6-7 deep levels were found in SA-samples with Atw of 1 and 3 , whereas the prevalent deep levels - in LA-samples with Atw of 6 and 30 . The critical twist

  13. Sheet resistance uniformity in drive-in step for different multi-crystalline silicon wafer dispositions

    Energy Technology Data Exchange (ETDEWEB)

    Moussi, A.; Bouhafs, D.; Mahiou, L. [Laboratoire des Cellules Photovoltaiques, Unite de Developpement de la Technologie du Silicium, 2 Bd, Frantz Fanon, B.P. 140, 7 Merveilles Alger (Algeria); Belkaid, M.S. [Dep. Electronique, Faculte de Genie Electrique et Informatique, UMMTO (Algeria)

    2009-09-15

    In this work, we present a study of emitters realized using different configurations of the silicon wafers in the quartz boat. The phosphorous liquid source is sprayed onto p-type multi-crystalline silicon substrates and the drive-in is made at high temperature in a muffle furnace. Three different configurations of the wafers in the boat are tested: separated, back to back and compact block of wafers. A fourth configuration is also used in source-receptor mode. The emitter phosphorous concentration profile is obtained by SIMS analysis. The resulting emitters are characterized by sheet resistance measurements and a comparison is made between the wafers within the same batch and from one batch to another. The uniformity and the standard deviation of the sheet resistance are calculated in each case. The emitter sheet resistance mapping of the wafer set in the middle of the boat for a given process gives a mean R{sub sq} 14.66 {omega}/sq with a standard deviation of 1.76% and uniformity of 18.7%. Standard deviations of 2.116% and 1.559% are obtained for wafers in the batch when using the spaced and compact configurations, respectively. The standard deviation is reduced to 0.68% when the wafers are used in source/receptor mode. A comparison is also made between wafers with different dilution of phosphorous source in ethanol. From these results we can conclude that the compact configuration offers better uniformity and lower standard deviation. Furthermore, when combined with the source-receptor configuration these parameters are significantly improved. This study allows the experimenter to identify the technological parameters of the solar cell emitter manufacturing and target precisely the desired values of the sheet resistance while limiting the number of rejected wafers. (author)

  14. Which patients with resectable pancreatic cancer truly benefit from oncological resection: is it destiny or biology?

    Science.gov (United States)

    Zheng, Lei; Wolfgang, Christopher L

    2015-01-01

    Pancreatic cancer has a dismal prognosis. A technically perfect surgical operation may still not provide a survival advantage for patients with technically resectable pancreatic cancer. Appropriate selection of patients for surgical resections is an imminent issue. Recent studies have provided an important clue on what serum biomarkers may be used to select out the patients who would unlikely benefit from the surgical resection.

  15. Characterization of perovskite layer on various nanostructured silicon wafer

    Science.gov (United States)

    Rostan, Nur Fairuz Mohd; Sepeai, Suhaila; Ramli, Noor Fadhilah; Azhari, Ayu Wazira; Ludin, Norasikin Ahmad; Teridi, Mohd Asri Mat; Ibrahim, Mohd Adib; Zaidi, Saleem H.

    2017-05-01

    Crystalline silicon (c-Si) solar cell dominates 90% of photovoltaic (PV) market. The c-Si is the most mature of all PV technologies and expected to remain leading the PV technology by 2050. The attractive characters of Si solar cell are stability, long lasting and higher lifetime. Presently, the efficiency of c-Si solar cell is still stuck at 25% for one and half decades. Tandem approach is one of the attempts to improve the Si solar cell efficiency with higher bandgap layer is stacked on top of Si bottom cell. Perovskite offers a big potential to be inserted into a tandem solar cell. Perovskite with bandgap of 1.6 to 1.9 eV will be able to absorb high energy photons, meanwhile c-Si with bandgap of 1.124 eV will absorb low energy photons. The high carrier mobility, high carrier lifetime, highly compatible with both solution and evaporation techniques makes perovskite an eligible candidate for perovskite-Si tandem configuration. The solution of methyl ammonium lead iodide (MAPbI3) was prepared by single step precursor process. The perovskite layer was deposited on different c-Si surface structure, namely planar, textured and Si nanowires (SiNWs) by using spin-coating technique at different rotation speeds. The nanostructure of Si surface was textured using alkaline based wet chemical etching process and SiNW was grown using metal assisted etching technique. The detailed surface morphology and absorbance of perovskite were studied in this paper. The results show that the thicknesses of MAPbI3 were reduced with the increasing of rotation speed. In addition, the perovskite layer deposited on the nanostructured Si wafer became rougher as the etching time and rotation speed increased. The average surface roughness increased from ˜24 nm to ˜38 nm for etching time range between 5-60 min at constant low rotation speed (2000 rpm) for SiNWs Si wafer.

  16. KELVIN PROBE SELF-CALIBRATION MODE FOR SEMICONDUCTOR WAFERS PROPERTIES MONITORING

    Directory of Open Access Journals (Sweden)

    R. I. Vorobey

    2014-01-01

    Full Text Available Improvement of repeatability and reliability of semiconductor wafers properties monitoring with a probe charge-sensitive methods is achieved by realization of Kelvin probe self-calibration mode using a wafer’s surface itself as a reference sample. Results of wafer surface scanning are visualized in the form of parameter distribution color map. A method of measurements based on Kelvin probe self-calibration mode is realized in a measurement installation for non-destructive non-contact monitoring of semiconductor wafer defects. Method can be used to define defects’ physical properties including minority carrier diffusion length and lifetime, trapped charge density and energy distribution etc.

  17. A modified occlusal wafer for managing partially dentate orthognathic patients--a case series.

    Science.gov (United States)

    Soneji, Bhavin Kiritkumar; Esmail, Zaid; Sharma, Pratik

    2015-03-01

    A multidisciplinary approach is essential in orthognathic surgery to achieve stable and successful outcomes. The model surgery planning is an important aspect in achieving the desired aims. An occlusal wafer used at the time of surgery aids the surgeon during correct placement of the jaws. When dealing with partially dentate patients, the design of the occlusal wafer requires modification to appropriately position the jaw. Two cases with partially dentate jaws are presented in which the occlusal wafer has been modified to provide stability at the time of surgery.

  18. Outcome of colorectal cancer resection in octogenarians

    African Journals Online (AJOL)

    elderly, age was not an independent contributor, and medical. Outcome of colorectal ... Introduction. Octogenarians constitute a rapidly growing segment of patients undergoing colorectal cancer resection, but their outcomes .... Characteristics of patients aged >80 years and 60 - 70 years undergoing colorectal resection.

  19. COMPARATIVE STUDY OF CONSERVATIVE RESECTION AND ...

    African Journals Online (AJOL)

    1999-05-05

    May 5, 1999 ... the histopathologic sub-type, stage, fixity of the tumour and on the experience of the surgeon. By and large, there are two widely divergent views concerning the extent of resection to be carried out in thyroid cancer; radical operation or conservative resection. Proponents of the radical operation (R-0) for ...

  20. 1366 Project Automate: Enabling Automation for <$0.10/W High-Efficiency Kerfless Wafers Manufactured in the US

    Energy Technology Data Exchange (ETDEWEB)

    Lorenz, Adam [1366 Technologies, Bedford, MA (United States)

    2017-05-10

    For photovoltaic (PV) manufacturing to thrive in the U.S., there must be an innovative core to the technology. Project Automate builds on 1366’s proprietary Direct Wafer® kerfless wafer technology and aims to unlock the cost and efficiency advantages of thin kerfless wafers. Direct Wafer is an innovative, U.S.-friendly (efficient, low-labor content) manufacturing process that addresses the main cost barrier limiting silicon PV cost-reductions – the 35-year-old grand challenge of manufacturing quality wafers (40% of the cost of modules) without the cost and waste of sawing. This simple, scalable process will allow 1366 to manufacture “drop-in” replacement wafers for the $10 billion silicon PV wafer market at 50% of the cost, 60% of the capital, and 30% of the electricity of conventional casting and sawing manufacturing processes. This SolarMat project developed the Direct Wafer processes’ unique capability to tailor the shape of wafers to simultaneously make thinner AND stronger wafers (with lower silicon usage) that enable high-efficiency cell architectures. By producing wafers with a unique target geometry including a thick border (which determines handling characteristics) and thin interior regions (which control light capture and electron transport and therefore determine efficiency), 1366 can simultaneously improve quality and lower cost (using less silicon).

  1. Adhesive disbond detection using piezoelectric wafer active sensors

    Science.gov (United States)

    Roth, William; Giurgiutiu, Victor

    2015-04-01

    The aerospace industry continues to increase the use of adhesives for structural bonding due to the increased joint efficiency (reduced weight), even distribution of the load path and decreases in stress concentrations. However, the limited techniques for verifying the strength of adhesive bonds has reduced its use on primary structures and requires an intensive inspection schedule. This paper discusses a potential structural health monitoring (SHM) technique for the detection of disbonds through the in situ inspection of adhesive joints. This is achieved through the use of piezoelectric wafer active sensors (PWAS), thin unobtrusive sensors which are permanently bonded to the aircraft structure. The detection method discussed in this study is electromechanical impedance spectroscopy (EMIS), a local vibration method. This method detects disbonds from the change in the mechanical impedance of the structure surrounding the disbond. This paper will discuss how predictive modeling can provide valuable insight into the inspection method, and provide better results than empirical methods alone. The inspection scheme was evaluated using the finite element method, and the results were verified experimentally using a large aluminum test article, and included both pristine and disbond coupons.

  2. Laser cleaning of silicon wafers: mechanisms and efficiencies

    Science.gov (United States)

    Mosbacher, Mario; Bertsch, M.; Muenzer, H.-J.; Dobler, V.; Runge, B.-U.; Baeuerle, Dieter; Boneberg, Johannes; Leiderer, Paul

    2002-02-01

    We report on experiments on the underlying physical mechanisms in the Dry-(DLC) and Steam Laser Cleaning (SLC) process. Using a frequency doubled, Q-switched Nd:YAG laser (FWHMequals8 ns), we removed polystyrene (PS) particles with diameters from 110-2000 nm from industrial silicon wafers by the DLC process. The experiments have been carried out both in ambient conditions as well as in high vacuum (10-6mbar) and the cleaned areas have been characterized by atomic force microscopy for damage inspection. Besides the determining the cleaning thresholds in laser fluence for a large interval of particle sizes we could show that particle removal in DLC is due to a combination of at least three effects: thermal substrate expansion, local substrate ablation due to field enhancement at the particle and explosive evaporation of absorbed humidity from the air. Which effect dominates the process is subject to the boundary conditions. For our laser parameters no damage free DLC was possible, i.e. whenever a particle was removed by DLC we damaged the substrate by local field enhancement. In our SLC experiments we determined the amount of superheating of a liquid layer adjacent to surfaces with controlled roughness that is necessary, in good agreement with theoretical predictions. Rough surfaces exhibited only a much smaller superheating.

  3. Biliary Stricture Following Hepatic Resection

    Directory of Open Access Journals (Sweden)

    Jeffrey B. Matthews

    1991-01-01

    Full Text Available Anatomic distortion and displacement of hilar structures due to liver lobe atrophy and hypertrophy occasionally complicates the surgical approach for biliary stricture repair. Benign biliary stricture following hepatic resection deserves special consideration in this regard because the inevitable hypertrophy of the residual liver causes marked rotation and displacement of the hepatic hilum that if not anticipated may render exposure for repair difficult and dangerous. Three patients with biliary stricture after hepatectomy illustrate the influence of hepatic regeneration on attempts at subsequent stricture repair. Following left hepatectomy, hypertrophy of the right and caudate lobes causes an anteromedial rotation and displacement of the portal structures. After right hepatectomy, the rotation is posterolateral, and a thoracoabdominal approach may be necessary for adequate exposure. Radiographs obtained in the standard anteroposterior projection may be deceptive, and lateral views are recommended to aid in operative planning.

  4. Safe Resection and Primary Anastomosis of Gangrenous Sigmoid ...

    African Journals Online (AJOL)

    %) of the sigmoid volvulus was gangrenous and 85.2% of all the sigmoid volvulus was managed by resection and primary anastomosis. Complications seen after resection and primary anastomosis were anastomotic leak at 4.5%, resection.

  5. Robust wafer identification recognition based on asterisk-shape filter and high-low score comparison method.

    Science.gov (United States)

    Hsu, Wei-Chih; Yu, Tsan-Ying; Chen, Kuan-Liang

    2009-12-10

    Wafer identifications (wafer ID) can be used to identify wafers from each other so that wafer processing can be traced easily. Wafer ID recognition is one of the problems of optical character recognition. The process to recognize wafer IDs is similar to that used in recognizing car license-plate characters. However, due to some unique characteristics, such as the irregular space between two characters and the unsuccessive strokes of wafer ID, it will not get a good result to recognize wafer ID by directly utilizing the approaches used in car license-plate character recognition. Wafer ID scratches are engraved by a laser scribe almost along the following four fixed directions: horizontal, vertical, plus 45 degrees , and minus 45 degrees orientations. The closer to the center line of a wafer ID scratch, the higher the gray level will be. These and other characteristics increase the difficulty to recognize the wafer ID. In this paper a wafer ID recognition scheme based on an asterisk-shape filter and a high-low score comparison method is proposed to cope with the serious influence of uneven luminance and make recognition more efficiently. Our proposed approach consists of some processing stages. Especially in the final recognition stage, a template-matching method combined with stroke analysis is used as a recognizing scheme. This is because wafer IDs are composed of Semiconductor Equipment and Materials International (SEMI) standard Arabic numbers and English alphabets, and thus the template ID images are easy to obtain. Furthermore, compared with the approach that requires prior training, such as a support vector machine, which often needs a large amount of training image samples, no prior training is required for our approach. The testing results show that our proposed scheme can efficiently and correctly segment out and recognize the wafer ID with high performance.

  6. Fabrication of capacitive absolute pressure sensor using Si-Au eutectic bonding in SOI wafer

    International Nuclear Information System (INIS)

    Lee, Kang Ryeol; Kim, Kunnyun; Park, Hyo-Derk; Kim, Yong Kook; Choi, Seung-Woo; Choi, Woo-Beom

    2006-01-01

    A capacitive absolute pressure sensor was fabricated using a large deflected diaphragm with a sealed vacuum cavity formed by removing handling silicon wafer and oxide layers from a SOI wafer after eutectic bonding of a silicon wafer to the SOI wafer. The deflected displacements of the diaphragm formed by the vacuum cavity in the fabricated sensor were similar to simulation results. Initial capacitance values were about 2.18pF and 3.65pF under normal atmosphere, where the thicknesses of the diaphragm used to fabricate the vacuum cavity were 20 μm and 30 μm, respectively. Also, it was confirmed that the differences of capacitance value from 1000hPa to 5hPa were about 2.57pF and 5.35pF, respectively

  7. A study of defects on EUV mask using blank inspection, patterned mask inspection, and wafer inspection

    Energy Technology Data Exchange (ETDEWEB)

    Huh, S.; Ren, L.; Chan, D.; Wurm, S.; Goldberg, K. A.; Mochi, I.; Nakajima, T.; Kishimoto, M.; Ahn, B.; Kang, I.; Park, J.-O.; Cho, K.; Han, S.-I.; Laursen, T.

    2010-03-12

    The availability of defect-free masks remains one of the key challenges for inserting extreme ultraviolet lithography (EUVL) into high volume manufacturing. yet link data is available for understanding native defects on real masks. In this paper, a full-field EUV mask is fabricated to investigate the printability of various defects on the mask. The printability of defects and identification of their source from mask fabrication to handling were studied using wafer inspection. The printable blank defect density excluding particles and patterns is 0.63 cm{sup 2}. Mask inspection is shown to have better sensitivity than wafer inspection. The sensitivity of wafer inspection must be improved using through-focus analysis and a different wafer stack.

  8. Boron implant profile variation across a single wafer due to electrostatic scanning

    International Nuclear Information System (INIS)

    Park, Changhae; Klein, K.M.; Tasch, A.F.; Simonton, R.B.; Kamenitsa, D.E.; Novak, S.

    1991-01-01

    The implanted impurity profile variation across a wafer due to an electrostatic scanning system has been studied for boron implants into (100) silicon wafers. The variation of the actual tilt and rotation angles across a wafer has been precisely determined for the implanter used in this study. The sensitivity of the impurity profiles to this angular variation has been studied through both a theoretical prediction based on an improved calculation of critical angles for channeling, and a qualitative analysis using the thermal wave measurement technique. A quantitative study of the profile variation across a wafer has also been performed using extensive secondary ion mass spectrometry (SIMS) profile measurements. For the energy range (15-80 keV) and angle range (0-10deg tilt angle, 0-360deg rotation angle) used in this study, we have identified the ranges of tilt and rotation angles that should be used for minimum channeling and minimum profile variation. (orig.)

  9. Effect of wafer bow on electrostatic chucking and back side gas cooling

    Science.gov (United States)

    Goodman, Daniel L.

    2008-12-01

    Electrostatic chucks (ESCs) are used in the semiconductor industry to clamp wafers to a pedestal and combined with back side gas (BSG) cooling to control temperature during processing. The effect of wafer bow in an ESC/BSG system is studied theoretically and experimentally. An equilibrium model is developed that predicts the maximum allowed bow for initial chucking and the maximum BSG pressure once the wafer is chucked. Experimental chucking and BSG pressure data show the maximum initial bow that can be chucked agree with model predictions. Hysteresis in pressure versus flow data is also consistent with the model. The model does not predict some features of thin wafers with highly stressed films. However, deviations between the model and data in this nonlinear regime are expected. By combining the theory with the experimental data, a method to determine a safe BSG/ESC operating range is given.

  10. Wafer level Integration on PolyStrata(R) Interposer (WIPI) (17013), Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Nuvotronics will develop a robust wafer-level integration technology using our proprietary PolyStrata interposer to enable high-frequency interconnects and routing...

  11. Clinicodemographic aspect of resectable pancreatic cancer and prognostic factors for resectable cancer

    Directory of Open Access Journals (Sweden)

    Chiang Kun-Chun

    2012-05-01

    Full Text Available Abstract Background Pancreatic adenocarcinoma (PCA is one of the most lethal human malignancies, and radical surgery remains the cornerstone of treatment. After resection, the overall 5-year survival rate is only 10% to 29%. At the time of presentation, however, about 40% of patients generally have distant metastases and another 40% are usually diagnosed with locally advanced cancers. The remaining 20% of patients are indicated for surgery on the basis of the results of preoperative imaging studies; however, about half of these patients are found to be unsuitable for resection during surgical exploration. In the current study, we aimed to determine the clinicopathological characteristics that predict the resectability of PCA and to conduct a prognostic analysis of PCA after resection to identify favorable survival factors. Methods We retrospectively reviewed the medical files of 688 patients (422 men and 266 women who had undergone surgery for histopathologically proven PCA in the Department of Surgery at Chang Gung Memorial Hospital in Taiwan from 1981 to 2006. We compared the clinical characteristics of patients who underwent resection and patients who did not undergo resection in order to identify the predictive factors for successful resectability of PCA, and we conducted prognostic analysis for PCA after resection. Results A carbohydrate antigen 19–9 (CA 19–9 level of 37 U/ml or greater and a tumor size of 3 cm or more independently predicted resectability of PCA. In terms of survival after resection, PCA patients with better nutritional status (measured as having an albumin level greater than 3.5 g/dl, radical resection, early tumor stage and better-differentiated tumors were associated with favorable survival. Conclusions Besides traditional imaging studies, preoperative CA 19–9 levels and tumor size can also be used to determine the resectability of PCA. Better nutritional status, curative resection, early tumor stage and well

  12. A front-end wafer-level microsystem packaging technique with micro-cap array

    Science.gov (United States)

    Chiang, Yuh-Min

    2002-09-01

    The back-end packaging process is the remaining challenge for the micromachining industry to commercialize microsystem technology (MST) devices at low cost. This dissertation presents a novel wafer level protection technique as a final step of the front-end fabrication process for MSTs. It facilitates improved manufacturing throughput and automation in package assembly, wafer level testing of devices, and enhanced device performance. The method involves the use of a wafer-sized micro-cap array, which consists of an assortment of small caps micro-molded onto a material with adjustable shapes and sizes to serve as protective structures against the hostile environments during packaging. The micro-cap array is first constructed by a micromachining process with micro-molding technique, then sealed to the device wafer at wafer level. Epoxy-based wafer-level micro cap array has been successfully fabricated and showed good compatibility with conventional back-end packaging processes. An adhesive transfer technique was demonstrated to seal the micro cap array with a MEMS device wafer. No damage or gross leak was observed while wafer dicing or later during a gross leak test. Applications of the micro cap array are demonstrated on MEMS, microactuators fabricated using CRONOS MUMPS process. Depending on the application needs, the micro-molded cap can be designed and modified to facilitate additional component functions, such as optical, electrical, mechanical, and chemical functions, which are not easily achieved in the device by traditional means. Successful fabrication of a micro cap array comprised with microlenses can provide active functions as well as passive protection. An optical tweezer array could be one possibility for applications of a micro cap with microlenses. The micro cap itself could serve as micro well for DNA or bacteria amplification as well.

  13. Electronically and ionically conductive porous material and method for manufacture of resin wafers therefrom

    Energy Technology Data Exchange (ETDEWEB)

    Lin, YuPo J [Naperville, IL; Henry, Michael P [Batavia, IL; Snyder, Seth W [Lincolnwood, IL

    2008-11-18

    An electrically and ionically conductive porous material including a thermoplastic binder and one or more of anion exchange moieties or cation exchange moieties or mixtures thereof and/or one or more of a protein capture resin and an electrically conductive material. The thermoplastic binder immobilizes the moieties with respect to each other but does not substantially coat the moieties and forms the electrically conductive porous material. A wafer of the material and a method of making the material and wafer are disclosed.

  14. Electronically and ionically conductive porous material and method for manufacture of resin wafers therefrom

    Science.gov (United States)

    Lin, YuPo J [Naperville, IL; Henry, Michael P [Batavia, IL; Snyder, Seth W [Lincolnwood, IL

    2011-07-12

    An electrically and ionically conductive porous material including a thermoplastic binder and one or more of anion exchange moieties or cation exchange moieties or mixtures thereof and/or one or more of a protein capture resin and an electrically conductive material. The thermoplastic binder immobilizes the moieties with respect to each other but does not substantially coat the moieties and forms the electrically conductive porous material. A wafer of the material and a method of making the material and wafer are disclosed.

  15. Silicon wafer wettability and aging behaviors: Impact on gold thin-film morphology

    KAUST Repository

    Yang, Xiaoming

    2014-10-01

    This paper reports on the wettability and aging behaviors of the silicon wafers that had been cleaned using a piranha (3:1 mixture of sulfuric acid (H2SO4, 96%) and hydrogen peroxide (H2O 2, 30%), 120 °C), SC1 (1:1:5 mixture of NH4OH, H 2O2 and H2O, at 80°C) or HF solution (6 parts of 40% NH4F and 1 part of 49% HF, at room temperature) solution, and treated with gaseous plasma. The silicon wafers cleaned using the piranha or SC1 solution were hydrophilic, and the water contact angles on the surfaces would increase along with aging time, until they reached the saturated points of around 70°. The contact angle increase rate of these wafers in a vacuum was much faster than that in the open air, because of loss of water, which was physically adsorbed on the wafer surfaces. The silicon wafers cleaned with the HF solution were hydrophobic. Their contact angle decreased in the atmosphere, while it increased in the vacuum up to 95°. Gold thin films deposited on the hydrophilic wafers were smoother than that deposited on the hydrophobic wafers, because the numerous oxygen groups formed on the hydrophilic surfaces would react with gold adatoms in the sputtering process to form a continuous thin film at the nucleation stage. The argon, nitrogen, oxygen gas plasma treatments could change the silicon wafer surfaces from hydrophobic to hydrophilic by creating a thin (around 2.5 nm) silicon dioxide film, which could be utilized to improve the roughness and adhesion of the gold thin film. © 2014 Elsevier Ltd. All rights reserved.

  16. In vitro and in vivo evaluation of a sublingual fentanyl wafer formulation

    Science.gov (United States)

    Lim, Stephen CB; Paech, Michael J; Sunderland, Bruce; Liu, Yandi

    2013-01-01

    Background The objective of this study was to prepare a novel fentanyl wafer formulation by a freeze-drying method, and to evaluate its in vitro and in vivo release characteristics, including its bioavailability via the sublingual route. Methods The wafer formulation was prepared by freeze-drying an aqueous dispersion of fentanyl containing sodium carboxymethylcellulose and amylogum as matrix formers. Uniformity of weight, friability, and dissolution testing of the fentanyl wafer was achieved using standard methods, and the residual moisture content was measured. The fentanyl wafer was also examined using scanning electron microscopy and x-ray diffraction. The absolute bioavailability of the fentanyl wafer was evaluated in 11 opioid-naïve adult female patients using a randomized crossover design. Results In vitro release showed that almost 90% of the fentanyl dissolved in one minute. In vivo, the first detectable plasma fentanyl concentration was observed after 3.5 minutes and the peak plasma concentration between 61.5 and 67 minutes. The median absolute bioavailability was 53.0%. Conclusion These results indicate that this wafer has potential as an alternative sublingual fentanyl formulation. PMID:23596347

  17. Nonuniformities of electrical resistivity in undoped 6H-SiC wafers

    International Nuclear Information System (INIS)

    Li, Q.; Polyakov, A.Y.; Skowronski, M.; Sanchez, E.K.; Loboda, M.J.; Fanton, M.A.; Bogart, T.; Gamble, R.D.

    2005-01-01

    Chemical elemental analysis, temperature-dependent Hall measurements, deep-level transient spectroscopy, and contactless resistivity mapping were performed on undoped semi-insulating (SI) and lightly nitrogen-doped conducting 6H-SiC crystals grown by physical vapor transport (PVT). Resistivity maps of commercial semi-insulating SiC wafers revealed resistivity variations across the wafers between one and two orders of magnitude. Two major types of variations were identified. First is the U-shape distribution with low resistivity in the center and high in the periphery of the wafer. The second type had an inverted U-shape distribution. Secondary-ion-mass spectrometry measurements of the distribution of nitrogen concentration along the growth axis and across the wafers sliced from different locations of lightly nitrogen-doped 6H-SiC boules were conducted. The measured nitrogen concentration gradually decreased along the growth direction and from the center to the periphery of the wafers. This change gives rise to the U-like distribution of resistivity in wafers of undoped SI-SiC. The concentrations of deep electron traps exhibited similar dependence. Compensation of nitrogen donors by these traps can result in the inverted U-like distribution of resistivity. Possible reasons for the observed nonuniformities include formation of a (0001) facet in PVT growth coupled with orientation-dependent nitrogen incorporation, systematic changes of the gas phase composition, and increase of the deposition temperature during boule growth

  18. A wafer mapping technique for residual stress in surface micromachined films

    International Nuclear Information System (INIS)

    Schiavone, G; Murray, J; Smith, S; Walton, A J; Desmulliez, M P Y; Mount, A R

    2016-01-01

    The design of MEMS devices employing movable structures is crucially dependant on the mechanical behaviour of the deposited materials. It is therefore important to be able to fully characterize the micromachined films and predict with confidence the mechanical properties of patterned structures. This paper presents a characterization technique that enables the residual stress in MEMS films to be mapped at the wafer level by using microstructures released by surface micromachining. These dedicated MEMS test structures and the associated measurement techniques are used to extract localized information on the strain and Young’s modulus of the film under investigation. The residual stress is then determined by numerically coupling this data with a finite element analysis of the structure. This paper illustrates the measurement routine and demonstrates it with a case study using electrochemically deposited alloys of nickel and iron, particularly prone to develop high levels of residual stress. The results show that the technique enables wafer mapping of film non-uniformities and identifies wafer-to-wafer differences. A comparison between the results obtained from the mapping technique and conventional wafer bow measurements highlights the benefits of using a procedure tailored to films that are non-uniform, patterned and surface-micromachined, as opposed to simple standard stress extraction methods. The presented technique reveals detailed information that is generally unexplored when using conventional stress extraction methods such as wafer bow measurements. (paper)

  19. Laser cutting sandwich structure glass-silicon-glass wafer with laser induced thermal-crack propagation

    Science.gov (United States)

    Cai, Yecheng; Wang, Maolu; Zhang, Hongzhi; Yang, Lijun; Fu, Xihong; Wang, Yang

    2017-08-01

    Silicon-glass devices are widely used in IC industry, MEMS and solar energy system because of their reliability and simplicity of the manufacturing process. With the trend toward the wafer level chip scale package (WLCSP) technology, the suitable dicing method of silicon-glass bonded structure wafer has become necessary. In this paper, a combined experimental and computational approach is undertaken to investigate the feasibility of cutting the sandwich structure glass-silicon-glass (SGS) wafer with laser induced thermal-crack propagation (LITP) method. A 1064 nm semiconductor laser cutting system with double laser beams which could simultaneously irradiate on the top and bottom of the sandwich structure wafer has been designed. A mathematical model for describing the physical process of the interaction between laser and SGS wafer, which consists of two surface heating sources and two volumetric heating sources, has been established. The temperature stress distribution are simulated by using finite element method (FEM) analysis software ABAQUS. The crack propagation process is analyzed by using the J-integral method. In the FEM model, a stationary planar crack is embedded in the wafer and the J-integral values around the crack front edge are determined using the FEM. A verification experiment under typical parameters is conducted and the crack propagation profile on the fracture surface is examined by the optical microscope and explained from the stress distribution and J-integral value.

  20. Borderline resectable pancreatic cancer: Definitions and management

    Science.gov (United States)

    Lopez, Nicole E; Prendergast, Cristina; Lowy, Andrew M

    2014-01-01

    Pancreatic cancer is the fourth leading cause of cancer death in the United States. While surgical resection remains the only curative option, more than 80% of patients present with unresectable disease. Unfortunately, even among those who undergo resection, the reported median survival is 15-23 mo, with a 5-year survival of approximately 20%. Disappointingly, over the past several decades, despite improvements in diagnostic imaging, surgical technique and chemotherapeutic options, only modest improvements in survival have been realized. Nevertheless, it remains clear that surgical resection is a prerequisite for achieving long-term survival and cure. There is now emerging consensus that a subgroup of patients, previously considered poor candidates for resection because of the relationship of their primary tumor to surrounding vasculature, may benefit from resection, particularly when preceded by neoadjuvant therapy. This stage of disease, termed borderline resectable pancreatic cancer, has become of increasing interest and is now the focus of a multi-institutional clinical trial. Here we outline the history, progress, current treatment recommendations, and future directions for research in borderline resectable pancreatic cancer. PMID:25152577

  1. Contemporary Management of Localized Resectable Pancreatic Cancer.

    Science.gov (United States)

    Kommalapati, Anuhya; Tella, Sri Harsha; Goyal, Gaurav; Ma, Wen Wee; Mahipal, Amit

    2018-01-20

    Pancreatic cancer is the third most common cause of cancer deaths in the United States. Surgical resection with negative margins still constitutes the cornerstone of potentially curative therapy, but is possible only in 15-20% of patients at the time of initial diagnosis. Accumulating evidence suggests that the neoadjuvant approach may improve R0 resection rate in localized resectable and borderline resectable diseases, and potentially downstage locally advanced disease to achieve surgical resection, though the impact on survival is to be determined. Despite advancements in the last decade in developing effective combinational chemo-radio therapeutic options, preoperative treatment strategies, and better peri-operative care, pancreatic cancer continues to carry a dismal prognosis in the majority. Prodigious efforts are currently being made in optimizing the neoadjuvant therapy with a better toxicity profile, developing novel agents, imaging techniques, and identification of biomarkers for the disease. Advancement in our understanding of the tumor microenvironment and molecular pathology is urgently needed to facilitate the development of novel targeted and immunotherapies for this setting. In this review, we detail the current literature on contemporary management of resectable, borderline resectable and locally advanced pancreatic cancer with a focus on future directions in the field.

  2. NXE:3100 full wafer imaging performance and budget verification

    Science.gov (United States)

    van Setten, Eelco; van Ingen Schenau, Koen; O'Mahony, Mark; Hollink, Thijs; Wittebrood, Friso; Davydova, Natalia; Eurlings, Mark; Feenstra, Kees; Finders, Jo; Dusa, Mircea; Young, Stuart

    2012-02-01

    With the introduction of the NXE:3100 NA=0.25 exposure system a big step has been made to get EUV lithography ready for High Volume Manufacturing. Over the last year, 6 exposure systems have been shipped to various customers around the world, active in Logic, DRAM, MPU and Flash memory, covering all major segments in the semi-conductor industry. The integration and qualification of these systems have provided a great learning, identifying the benefits of EUV over ArF immersion and the critical parameters of the exposure tool and how to operate it. In this paper we will focus specifically on the imaging performance of the NXE:3100 EUV scanner. Having been operational for more than a year a wide range of features were evaluated for lithographic performance across the field and across wafer. CD results of 32nm contact holes, 27nm isolated and dense lines, 27nm two-bar, 22nm dense L/S with Dipole, as well as several device features will be discussed and benchmarked against the current ArF immersion performance. A budget verification will be presented showing CD and contrast budgets for a selection of lithographic features. The contribution of the resist process and the mask will be discussed as well. The litho performance optimization will be highlighted with the 27nm twobar and isolated lines features that are sensitive to the illuminator pupil shape and projection lens aberrations. We will estimate the amount of resist induced contrast loss for 27 and 22nm L/S based on measurements of Exposure Latitude and the contributors from the exposure system. We will further present on the impact of variations in the mask blank and patterned mask on imaging, with several new contributors to take into account compared to traditional transmission masks. Finally, the combined results will be projected to the NXE:3300 NA=0.33 exposure system to give an outlook for its imaging performance capabilities.

  3. DynAMITe: a wafer scale sensor for biomedical applications

    International Nuclear Information System (INIS)

    Esposito, M; Wells, K; Anaxagoras, T; Fant, A; Allinson, N M; Konstantinidis, A; Speller, R D; Osmond, J P F; Evans, P M

    2011-01-01

    In many biomedical imaging applications Flat Panel Imagers (FPIs) are currently the most common option. However, FPIs possess several key drawbacks such as large pixels, high noise, low frame rates, and excessive image artefacts. Recently Active Pixel Sensors (APS) have gained popularity overcoming such issues and are now scalable up to wafer size by appropriate reticule stitching. Detectors for biomedical imaging applications require high spatial resolution, low noise and high dynamic range. These figures of merit are related to pixel size and as the pixel size is fixed at the time of the design, spatial resolution, noise and dynamic range cannot be further optimized. The authors report on a new rad-hard monolithic APS, named DynAMITe (Dynamic range Adjustable for Medical Imaging Technology), developed by the UK MI-3 Plus consortium. This large area detector (12.8 cm × 12.8 cm) is based on the use of two different diode geometries within the same pixel array with different size pixels (50 μm and 100 μm). Hence the resulting device can possess two inherently different resolutions each with different noise and saturation performance. The small and the large pixel cameras can be reset at different voltages, resulting in different depletion widths. The larger depletion width for the small pixels allows the initial generated photo-charge to be promptly collected, which ensures an intrinsically lower noise and higher spatial resolution. After these pixels reach near saturation, the larger pixels start collecting so offering a higher dynamic range whereas the higher noise floor is not important as at higher signal levels performance is governed by the Poisson noise of the incident radiation beam. The overall architecture and detailed characterization of DynAMITe will be presented in this paper.

  4. Augmented reality in a tumor resection model.

    Science.gov (United States)

    Chauvet, Pauline; Collins, Toby; Debize, Clement; Novais-Gameiro, Lorraine; Pereira, Bruno; Bartoli, Adrien; Canis, Michel; Bourdel, Nicolas

    2018-03-01

    Augmented Reality (AR) guidance is a technology that allows a surgeon to see sub-surface structures, by overlaying pre-operative imaging data on a live laparoscopic video. Our objectives were to evaluate a state-of-the-art AR guidance system in a tumor surgical resection model, comparing the accuracy of the resection with and without the system. Our system has three phases. Phase 1: using the MRI images, the kidney's and pseudotumor's surfaces are segmented to construct a 3D model. Phase 2: the intra-operative 3D model of the kidney is computed. Phase 3: the pre-operative and intra-operative models are registered, and the laparoscopic view is augmented with the pre-operative data. We performed a prospective experimental study on ex vivo porcine kidneys. Alginate was injected into the parenchyma to create pseudotumors measuring 4-10 mm. The kidneys were then analyzed by MRI. Next, the kidneys were placed into pelvictrainers, and the pseudotumors were laparoscopically resected. The AR guidance system allows the surgeon to see tumors and margins using classical laparoscopic instruments, and a classical screen. The resection margins were measured microscopically to evaluate the accuracy of resection. Ninety tumors were segmented: 28 were used to optimize the AR software, and 62 were used to randomly compare surgical resection: 29 tumors were resected using AR and 33 without AR. The analysis of our pathological results showed 4 failures (tumor with positive margins) (13.8%) in the AR group, and 10 (30.3%) in the Non-AR group. There was no complete miss in the AR group, while there were 4 complete misses in the non-AR group. In total, 14 (42.4%) tumors were completely missed or had a positive margin in the non-AR group. Our AR system enhances the accuracy of surgical resection, particularly for small tumors. Crucial information such as resection margins and vascularization could also be displayed.

  5. Endoscopic full-thickness resection: Current status.

    Science.gov (United States)

    Schmidt, Arthur; Meier, Benjamin; Caca, Karel

    2015-08-21

    Conventional endoscopic resection techniques such as endoscopic mucosal resection or endoscopic submucosal dissection are powerful tools for treatment of gastrointestinal neoplasms. However, those techniques are restricted to superficial layers of the gastrointestinal wall. Endoscopic full-thickness resection (EFTR) is an evolving technique, which is just about to enter clinical routine. It is not only a powerful tool for diagnostic tissue acquisition but also has the potential to spare surgical therapy in selected patients. This review will give an overview about current EFTR techniques and devices.

  6. P/N InP solar cells on Ge wafers

    Science.gov (United States)

    Wojtczuk, Steven; Vernon, Stanley; Burke, Edward A.

    1994-01-01

    Indium phosphide (InP) P-on-N one-sun solar cells were epitaxially grown using a metalorganic chemical vapor deposition process on germanium (Ge) wafers. The motivation for this work is to replace expensive InP wafers, which are fragile and must be thick and therefore heavy, with less expensive Ge wafers, which are stronger, allowing use of thinner, lighter weight wafers. An intermediate InxGs1-xP grading layer starting as In(0.49)Ga(0.51) at the GaAs-coated Ge wafer surface and ending as InP at the top of the grading layer (backside of the InP cell) was used to attempt to bend some of the threading dislocations generated by lattice-mismatch between the Ge wafer and InP cell so they would be harmlessly confined in this grading layer. The best InP/Ge cell was independently measured by NASA-Lewis with a one-sun 25 C AMO efficiently measured by NASA-Lewis with a one-circuit photocurrent 22.6 mA/sq cm. We believe this is the first published report of an InP cell grown on a Ge wafer. Why get excited over a 9 percent InP/Ge cell? If we look at the cell weight and efficiency, a 9 percent InP cell on an 8 mil Ge wafer has about the same cell power density, 118 W/kg (BOL), as the best InP cell ever made, a 19 percent InP cell on an 18 mil InP wafer, because of the lighter Ge wafer weight. As cell panel materials become lighter, the cell weight becomes more important, and the advantage of lightweight cells to the panel power density becomes more important. In addition, although InP/Ge cells have a low beginning-of-life (BOL) efficiency due to dislocation defects, the InP/Ge cells are very radiation hard (end-of-life power similar to beginning-of-life). We have irradiated an InP/Ge cell with alpha particles to an equivalent fluence of 1.6 x 10(exp 16) 1 MeV electrons/sq cm and the efficiency is still 83 percent of its BOL value. At this fluence level, the power output of these InP/Ge cells matches the GaAs/Ge cell data tabulated in the JPL handbook. Data are presented

  7. Optimizing Adjuvant Therapy for Resected Pancreatic Cancer

    Science.gov (United States)

    In this clinical trial, patients with resected pancreatic head cancer will be randomly assigned to receive either gemcitabine with or without erlotinib for 5 treatment cycles. Patients who do not experience disease progression or recurrence will then be r

  8. Laparoscopic liver resection for intrahepatic cholangiocarcinoma.

    Science.gov (United States)

    Uy, Billy James; Han, Ho-Seong; Yoon, Yoo-Seok; Cho, Jai Young

    2015-04-01

    Reports on laparoscopic liver resection for intrahepatic cholangiocarcinoma are still scarce. With increased experience in laparoscopic liver resection, its application to intrahepatic cholangiocarcinoma can now be considered. Our aim is to determine the feasibility and safety of laparoscopic liver resection for intrahepatic cholangiocarcinoma and to analyze its clinical and oncologic outcomes. Among the 84 patients with intrahepatic cholangiocarcinoma operated on from March 2004 to April 2012, 37 patients with a T-stage of 2b or less were included in the study. Eleven patients underwent laparoscopic liver resection, and 26 underwent open liver resection. Treatment and survival outcomes were analyzed. Intraoperative blood loss was significantly greater in the open group (P=.024), but with no difference in the blood transfusion requirement between groups (P=.074), and no operative mortality occurred. The median operative time, postoperative resection margin, and length of hospital stay were comparable between groups (P=.111, P=.125, and P=.077, respectively). Four (36.4%) patients in the laparoscopic group developed recurrence compared with 12 (46.2%) patients in the open group (P=.583). After a median follow-up of 17 months, the 3- and 5-year overall survival rates were 77.9% and 77.9%, respectively, in the laparoscopic group compared with 66.2% and 66.2%, respectively, in the open group (P=.7). There was also no significant difference in the 3- and 5-year disease-free survival rates for the laparoscopic group at 56.2% and 56.2%, respectively, versus the open group at 39.4% and 39.4%, respectively (P=.688). Laparoscopic liver resection for intrahepatic cholangiocarcinoma is technically safe with survival outcome comparable to that of open liver resection in selected cases.

  9. Open resections for congenital lung malformations

    Directory of Open Access Journals (Sweden)

    Mullassery Dhanya

    2008-01-01

    Full Text Available Aim: Pediatric lung resection is a relatively uncommon procedure that is usually performed for congenital lesions. In recent years, thoracoscopic resection has become increasingly popular, particularly for small peripheral lesions. The aim of this study was to review our experience with traditional open lung resection in order to evaluate the existing "gold standard." Materials and Methods: We carried out a retrospective analysis of all children having lung resection for congenital lesions at our institution between 1997 and 2004. Data were collected from analysis of case notes, operative records and clinical consultation. The mean follow-up was 37.95 months. The data were analyzed using SPSS. Results: Forty-one children (13 F/28 M underwent major lung resections during the study period. Their median age was 4.66 months (1 day-9 years. The resected lesions included 21 congenital cystic adenomatoid malformations, 14 congenital lobar emphysema, four sequestrations and one bronchogenic cyst. Fifty percent of the lesions were diagnosed antenatally. Twenty-six patients had a complete lobectomy while 15 patients had parenchymal sparing resection of the lesion alone. Mean postoperative stay was 5.7 days. There have been no complications in any of the patients. All patients are currently alive, asymptomatic and well. None of the patients have any significant chest deformity. Conclusions: We conclude that open lung resection enables parenchymal sparing surgery, is versatile, has few complications and produces very good long-term results. It remains the "gold standard" against which minimally invasive techniques may be judged.

  10. Rinsing of wafers after wet processing: Simulation and experiments

    Science.gov (United States)

    Chiang, Chieh-Chun

    In semiconductor manufacturing, a large amount (50 billion gallons for US semiconductor fabrication plants in 2006) of ultrapure water (UPW) is used to rinse wafers after wet chemical processing to remove ionic contaminants on surfaces. Of great concern are the contaminants left in narrow (tens of nm), high-aspect-ratio (5:1 to 20:1) features (trenches, vias, and contact holes). The International Technology Roadmap for Semiconductors (ITRS) stipulates that ionic contaminant levels be reduced to below ˜ 10 10 atoms/cm2. Understanding the bottlenecks in the rinsing process would enable conservation of rinse water usage. A comprehensive process model has been developed on the COMSOL platform to predict the dynamics of rinsing of narrow structures on patterned SiO 2 substrates initially cleaned with NH4OH. The model considers the effect of various mass-transport mechanisms, including convection and diffusion/dispersion, which occur simultaneously with various surface phenomena, such as adsorption and desorption of impurities. The influences of charged species in the bulk and on the surface, and their induced electric field that affect both transport and surface interactions, have been addressed. Modeling results show that the efficacy of rinsing is strongly influenced by the rate of desorption of adsorbed contaminants, mass transfer of contaminants from the mouth of the feature to the bulk liquid, and the trench aspect ratio. Detection of the end point of rinsing is another way to conserve water used for rinsing after wet processing. The applicability of electrochemical impedance spectroscopy (EIS) to monitor rinsing of Si processed in HF with and without copper contaminant was explored. In the first study, the effect of the nature of surface state (flat band, depletion, or accumulation) of silicon on rinsing rate was investigated. The experimental results show that the state of silicon could affect rinsing kinetics through modulation of ion adsorption. In the second

  11. Determination of ultra-trace contaminants on silicon wafer surfaces using TXRF. Present state of the art

    International Nuclear Information System (INIS)

    Pahlke, S.; Fabry, L.; Kotz, L.; Mantler, C.; Ehmann, T.

    2000-01-01

    Recently, TXRF became a standard, on-line inspection tool for controlling the cleanliness of polished Si wafers for semiconductor use now up to 300 diameter. Wafer makers strive for an all-over metallic cleanliness of 10 atoms x cm -2 . Therefore an analytical tools must cover LOD in a range 9 atoms x cm -2 or lower. The all-over cleanliness of the whole wafer surface can analyzed using VPD/TXRF. For this chemical wafer-pre-preparation under cleanroom conditions class 1 we have developed a full automatic 'Wafer Surface Preparation System' coupled with a new generation TXRF. We have also combined this system with other independent methods for Na, Al, anions and cations. Only the combination of automatic wafer handling systems, modem analytical tools, ultra-pure water, ULSI chemicals and special cleanroom conditions provides us a chance to achieve the present and the future demands for semiconductor industry. (author)

  12. Spatial characterization of a 2 in GaN wafer by Raman spectroscopy and capacitance-voltage measurements

    International Nuclear Information System (INIS)

    Huang, Y; Chen, X D; Fung, S; Beling, C D; Ling, C C

    2004-01-01

    Micro-Raman spectroscopy and capacitance-voltage (C-V) measurements have been used to investigate 2 in GaN epitaxial wafers grown by hydride vapour phase epitaxy on sapphire substrates. The position and line shape of the A 1 longitudinal optical (LO) phonon mode were used to determine the carrier concentration at different locations across the wafer. The line-shape fitting of the Raman A 1 (LO) coupled modes taken from horizontal lateral-different positions on the wafer yielded a rudimentary spatial map of the carrier concentration. These data compare well with a carrier density map of the wafer obtained by C-V measurements, confirming the non-uniform distribution of carrier concentration in the GaN epitaxial film and that Raman spectroscopy of the LO phonon-plasmon mode can be used as a reliable and production friendly wafer quality test for GaN wafer manufacturing processes

  13. Front-end wafer-level microsystem packaging technique with microcap array

    Science.gov (United States)

    Chiang, Yuh-Min; Bachman, Mark; Li, Guann-pyng

    2002-07-01

    Packaging represents a significant and expensive obstacle in commercializing microsystem technology (MST) devices such as micro-electro-mechanical systems (MEMS), micro-optical-electro-mechanical-systems (MOEMS), microsensors, microactuators and other micromachined devices. This paper describes a novel wafer level protection method for MST devices which facilitates improved manufacturing throughput and automation in package assembly, wafer level testing of devices, and enhanced device performance. The method involves the use of a wafer-sized micro-cap array. This array consists of an assortment of small caps molded onto a material with adjustable shapes and sizes to serve as protective structures against the hostile environments associated with packaging. It may also include modifications which enhance its adhesion to the MST wafer or increase the MST device function. Depending on the application, the micro-molded cap can be designed and modified to facilitate additional functions, such as optical, electrical, mechanical, and chemical functions, which are not easily achieved in the device by traditional means. The fabrication method, materials selection, and the compatibility of the micro cap device to conventional packaging process are discussed in this paper. The results of wafer-level micro cap packaging demonstrations are also presented.

  14. Dissolving oral clonazepam wafers in the acute treatment of prolonged seizures.

    Science.gov (United States)

    Troester, Matthew M; Hastriter, Eric V; Ng, Yu-Tze

    2010-12-01

    Klonopin (clonazepam; Genentech Inc, South San Francisco, California) oral wafers are benzodiazepines with anticonvulsive and anxiolytic properties. Our institution has been prescribing clonazepam wafers for acute treatment of prolonged seizures for years. Patients' size determined dosing at 0.25, 0.5, 1, or 2 mg wafers. We proceeded to obtain evidence for efficacy. Hospital Institutional Review Board approval was obtained for anonymous patient survey. All children who had been prescribed clonazepam wafers over a 6-year period at our institution were mailed detailed questionnaires. Three hundred eighty-one questionnaires were mailed with 88 replies but only 56 with meaningful data. Average age was 12.1 years. There were 31 males. Efficacy was defined as stopping seizure within 10 minutes, >50% of the time. Thirty-eight of the 56 (68%) patients met this criterion. From these 38 patients, 19 (50%) had seizures stop within 1 minute. Overall results were comparable to Diastat (rectal diazepam; Valeant Pharmaceuticals International, Aliso Viejo, California). Clonazepam wafers are an effective acute therapy for prolonged seizures.

  15. Grain-boundary type and distribution in silicon carbide coatings and wafers

    Science.gov (United States)

    Cancino-Trejo, Felix; López-Honorato, Eddie; Walker, Ross C.; Ferrer, Romelia Salomon

    2018-03-01

    Silicon carbide is the main diffusion barrier against metallic fission products in TRISO (tristructural isotropic) coated fuel particles. The explanation of the accelerated diffusion of silver through SiC has remained a challenge for more than four decades. Although, it is now well accepted that silver diffuse through SiC by grain boundary diffusion, little is known about the characteristics of the grain boundaries in SiC and how these change depending on the type of sample. In this work five different types (coatings and wafers) of SiC produced by chemical vapor deposition were characterized by electron backscatter diffraction (EBSD). The SiC in TRISO particles had a higher concentration of high angle grain boundaries (aprox. 70%) compared to SiC wafers, which ranged between 30 and 60%. Similarly, SiC wafers had a higher concentration of low angle grain boundaries ranging between 15 and 30%, whereas TRISO particles only reached values of around 7%. The same trend remained when comparing the content of coincidence site lattice (CSL) boundaries, since SiC wafers showed a concentration of more than 30%, whilst TRISO particles had contents of around 20%. In all samples the largest fractions of CSL boundaries (3 ≤ Σ ≤ 17) were the Σ3 boundaries. We show that there are important differences between the SiC in TRISO particles and SiC wafers which could explain some of the differences observed in diffusion experiments in the literature.

  16. Palladium-based on-wafer electroluminescence studies of GaN-based LED structures

    Energy Technology Data Exchange (ETDEWEB)

    Salcianu, C.O.; Thrush, E.J.; Humphreys, C.J. [Department of Materials Science and Metallurgy, University of Cambridge, Pembroke Street, Cambridge CB2 3QZ (United Kingdom); Plumb, R.G. [Centre for Photonic Systems, Department of Engineering, University of Cambridge, Cambridge CB3 0FD (United Kingdom); Boyd, A.R.; Rockenfeller, O.; Schmitz, D.; Heuken, M. [AIXTRON AG, Kackertstr. 15-17, 52072 Aachen (Germany)

    2008-07-01

    Electroluminescence (EL) testing of Light Emitting Diode (LED) structures is usually done at the chip level. Assessing the optical and electrical properties of LED structures at the wafer scale prior to their processing would improve the cost effectiveness of producing LED-lamps. A non-destructive method for studying the luminescence properties of the structure at the wafer-scale is photoluminescence (PL). However, the relationship between the on-wafer PL data and the final device EL can be less than straightforward (Y. H Aliyu et al., Meas. Sci. Technol. 8, 437 (1997)) as the two techniques employ different carrier injection mechanisms. This paper provides an overview of some different techniques in which palladium is used as a contact in order to obtain on-wafer electroluminescence information which could be used to screen wafers prior to processing into final devices. Quick mapping of the electrical and optical characteristics was performed using either palladium needle electrodes directly, or using the latter in conjunction with evaporated palladium contacts to inject both electrons and holes into the active region via the p-type capping layer of the structure. For comparison, indium was also used to make contact to the n-layer so that electrons could be directly injected into that layer. (copyright 2008 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim) (orig.)

  17. GeSn-on-insulator substrate formed by direct wafer bonding

    Energy Technology Data Exchange (ETDEWEB)

    Lei, Dian; Wang, Wei; Gong, Xiao, E-mail: elegong@nus.edu.sg, E-mail: yeo@ieee.org; Yeo, Yee-Chia, E-mail: elegong@nus.edu.sg, E-mail: yeo@ieee.org [Department of Electrical and Computer Engineering, National University of Singapore, Singapore 117576 (Singapore); Lee, Kwang Hong; Wang, Bing [Low Energy Electronic Systems (LEES), Singapore MIT Alliance for Research and Technology (SMART), 1 CREATE Way, #10-01 CREATE Tower, Singapore 138602 (Singapore); Bao, Shuyu [Low Energy Electronic Systems (LEES), Singapore MIT Alliance for Research and Technology (SMART), 1 CREATE Way, #10-01 CREATE Tower, Singapore 138602 (Singapore); School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore); Tan, Chuan Seng [School of Electrical and Electronic Engineering, Nanyang Technological University, 50 Nanyang Avenue, Singapore 639798 (Singapore)

    2016-07-11

    GeSn-on-insulator (GeSnOI) on Silicon (Si) substrate was realized using direct wafer bonding technique. This process involves the growth of Ge{sub 1-x}Sn{sub x} layer on a first Si (001) substrate (donor wafer) followed by the deposition of SiO{sub 2} on Ge{sub 1-x}Sn{sub x}, the bonding of the donor wafer to a second Si (001) substrate (handle wafer), and removal of the Si donor wafer. The GeSnOI material quality is investigated using high-resolution transmission electron microscopy, high-resolution X-ray diffraction (HRXRD), atomic-force microscopy, Raman spectroscopy, and spectroscopic ellipsometry. The Ge{sub 1-x}Sn{sub x} layer on GeSnOI substrate has a surface roughness of 1.90 nm, which is higher than that of the original Ge{sub 1-x}Sn{sub x} epilayer before transfer (surface roughness is 0.528 nm). The compressive strain of the Ge{sub 1-x}Sn{sub x} film in the GeSnOI is as low as 0.10% as confirmed using HRXRD and Raman spectroscopy.

  18. Thermal effect induced wafer deformation in high-energy e-beam lithography

    Science.gov (United States)

    Chen, P. S.; Wang, W. C.; Lin, S. J.

    2015-03-01

    The incident surface power density in Massive Electron-beam Direct Write (MEBDW) during exposure is ~105 W/cm2, much higher than ~8 W/cm2 ArF scanners and 2.4 W/cm2 EUV. In addition, the wafer's exposure in vacuum environment makes energy dissipation even harder. This thermal effect can cause mechanical distortion of the wafer during exposure and have has a direct influence on pattern placement error and image blur. In this paper, the thermo mechanical distortions caused by wafer heating for MEB system of different electron acceleration voltages have been simulated with finite element method (FEM). The global thermal effect affected by the friction force between the wafer and the wafer chuck as well as different thermal conductivities of the chuck material are simulated. Furthermore, the thermal effects of different lithography systems such as EUV scanners and conventional optical scanners are compared. The thermal effects of MEBDW systems are shown to be acceptable.

  19. Bonding of Si wafers by surface activation method for the development of high efficiency high counting rate radiation detectors

    International Nuclear Information System (INIS)

    Kanno, Ikuo; Yamashita, Makoto; Onabe, Hideaki

    2006-01-01

    Si wafers with two different resistivities ranging over two orders of magnitude were bonded by the surface activation method. The resistivities of bonded Si wafers were measured as a function of annealing temperature. Using calculations based on a model, the interface resistivities of bonded Si wafers were estimated as a function of the measured resistivities of bonded Si wafers. With thermal treatment from 500degC to 900degC, all interfaces showed high resistivity, with behavior that was close to that of an insulator. Annealing at 1000degC decreased the interface resistivity and showed close to ideal bonding after thermal treatment at 1100degC. (author)

  20. Change in Eyelid Position Following Muller's Muscle Conjunctival Resection With a Standard Versus Variable Resection Length.

    Science.gov (United States)

    Rootman, Daniel B; Sinha, Kunal R; Goldberg, Robert A

    2017-09-12

    This study compares the use of a standard 7 mm resection length to a variable 4:1 ratio of resection length to desired elevation nomogram when performing Muller's muscle conjunctival resection surgery. In this cross-sectional case control study, 2 groups were defined. The first underwent Muller's muscle conjunctival resection surgery with a standard 7 mm resection length and the second underwent the same surgery with a variable resection length determined by a 4:1 ratio of resection length to desired elevation nomogram. Groups were matched for age (within 5 years) and sex. Pre- and postoperative photographs were measured digitally. Change in upper marginal reflex distance 1 (MRD1) and final MRD1 were the primary outcome measures. The study was powered to detect a 1 mm difference in MRD1 to a beta error of 0.95. No significant preoperative differences between the groups were noted. No significant difference in final MRD1 (0.1 mm; p = 0.74) or change in MRD1 (0.2 mm; p = 0.52) was noted. Mean resection length to elevation ratios were 3.9:1 for standard group and 4.3:1 for the variable group (p = 0.54). The authors were not able to detect a significant difference in final MRD1 or change in MRD1 for patients undergoing Muller's muscle conjunctival resection surgery with standard or variable resection lengths. These results tend to argue against a purely mechanical mechanism for Muller's muscle conjunctival resection surgery.

  1. Treatment Strategy after Incomplete Endoscopic Resection of Early Gastric Cancer

    OpenAIRE

    Kim, Sang Gyun

    2016-01-01

    Endoscopic resection of early gastric cancer is defined as incomplete when tumor cells are found at the resection margin upon histopathological examination. However, a tumor-positive resection margin does not always indicate residual tumor; it can also be caused by tissue contraction during fixation, by the cautery effect during endoscopic resection, or by incorrect histopathological mapping. Cases of highly suspicious residual tumor require additional endoscopic or surgical resection. For in...

  2. Prospective evaluation of laparoscopic colon resection versus open colon resection for adenocarcinoma. A multicenter study.

    Science.gov (United States)

    Franklin, M E; Rosenthal, D; Norem, R F

    1995-07-01

    Laparoscopic colon resection (LCR) has been performed in the United States sine 1990. This procedure has been accepted by many as a reasonable alternative for nonmalignant, colonic, surgical disease, but the laparoscopic approach remains controversial for curative treatment of carcinoma. In this paper, the results of a nonrandomized series of two large experiences of laparoscopic colon resections were performed and followed for 3 1/2 years in a prospective fashion against an equal number of patients who underwent open resection. The setting was several large metropolitan hospitals in San Antonio, Texas. Over 194 patients were involved in this study. Each patient once diagnosed with resectable colonic cancer was allowed to choose their own procedure, laparoscopic or open colon resection, either of which was performed by the authors. Factors considered include age, sex, body habitus, stage of cancer, margins of resection, numbers of lymph nodes retrieved, hospitalization time, and follow-up period. Observations at this time indicate the following: (1) LCR allows for resection comparable to the classical approach, (2) equal numbers of mesenteric lymph nodes can be retrieved, (3) adequacy of margins of resection can be accurately determined by colonoscopy during LCR, and (4) brief follow-up periods show comparable survival and disease-free intervals. It is the conclusion of the authors that with proper training LCR will come to be recognized as a safe, effective surgical option for treatment of selected patients with colon cancer.

  3. Re-resection of remnant Caroli syndrome six years after the first resection (case report

    Directory of Open Access Journals (Sweden)

    Ahmed Zidan

    2016-01-01

    Conclusion: Imaging is essential in planning the operative treatment to detect the extent of the Caroli disease and define the extent of resection. Any residual disease due to inappropriate imaging planning may cost the patient another cycle of suffering and may need another surgical intervention as in our case. We recommend using intraoperative ultrasound for accurate determination of the line of resection.

  4. Recurrence after thymoma resection according to the extent of the resection

    Science.gov (United States)

    2014-01-01

    Background Complete resection of the thymus is considered appropriate for a thymoma resection because any remaining thymic tissue can lead to local recurrence. However, there are few studies concerning the extent of thymus resection. Therefore, we conducted a retrospective study to investigate whether recurrence following thymoma resection correlated to the extent of resection. Methods Between 1986 and 2011, a total of 491 patients underwent resection of thymic epithelial tumors with curative intent. Of those, we excluded patients with an undetermined World Health Organization (WHO) histologic type, patients with type C thymoma, and patients who underwent incomplete resection (n = 21). The remaining 342 patients were reviewed retrospectively and compared recurrence according to the extent of resection. Results Extended thymectomy was performed in 239 patients (69.9%) and limited thymectomy was performed 103 patients (30.1%). In the extended thymectomy group, 29 recurrences occurred, and in the limited thymectomy group, 10 recurrences occurred. Comparing rates of freedom from recurrence between two groups, there was no significant statistical difference in total recurrence (p =0.472) or local recurrence (p =0.798). After matching patients by stage and tumor size, there was no significant difference in freedom from recurrence between the two groups (p = 0.162). Additionally, after adjusting for histologic type and MG, there was also no significant difference (p = 0.125) between groups. Conclusions No difference in the rate of recurrence was observed in patients following limited thymectomy compared with extended thymectomy. PMID:24646138

  5. An electron-multiplying "Micromegas" grid made in silicon wafer post-processing technology

    CERN Document Server

    Chefdeville, M; Giomataris, Ioanis; van der Graaf, H; Heijne, Erik H M; Van der Putten, S; Salm, C; Schmitz, J; Smits, S; Timmermans, J; Visschers, J L

    2006-01-01

    A technology for manufacturing an aluminium grid onto a silicon wafer has been developed. The grid is fixed parallel and precisely to the wafer (anode) surface at a distance of 50 \\mum by means of insulating pillars. When some 400 V are applied between the grid and (anode) wafer, gas multiplication occurs : primary electrons from the drift space above the grid enter the holes and cause electron avalanches in the high-field region between the grid and the anode. Production and operational characteristics of the device are described. With this newly developed technology, CMOS (pixel) readout chips can be covered with a gas multiplication grid. Such a chip forms, together with the grid, an integrated device which can be applied as readout in a wide field of gaseous detectors.

  6. Feature profile evolution in plasma processing using on-wafer monitoring system

    CERN Document Server

    Samukawa, Seiji

    2014-01-01

    This book provides for the first time a good understanding of the etching profile technologies that do not disturb the plasma. Three types of sensors are introduced: on-wafer UV sensors, on-wafer charge-up sensors and on-wafer sheath-shape sensors in the plasma processing and prediction system of real etching profiles based on monitoring data. Readers are made familiar with these sensors, which can measure real plasma process surface conditions such as defect generations due to UV-irradiation, ion flight direction due to charge-up voltage in high-aspect ratio structures and ion sheath conditions at the plasma/surface interface. The plasma etching profile realistically predicted by a computer simulation based on output data from these sensors is described.

  7. AFM study of hippocampal cells cultured on silicon wafers with nano-scale surface topograph.

    Science.gov (United States)

    Ma, J; Liu, B F; Xu, Q Y; Cui, F Z

    2005-08-01

    The rat hippocampal cells were selected as model to study the interaction between the neural cells and silicon substrates using atomic force microscopy (AFM). The hippocampal cells show tight adherence on silicon wafers with nano-scale surface topograph. The lateral friction force investigated by AFM shows significant increase on the boundary around the cellular body. It is considered to relate to the cytoskeleton and cellular secretions. After ultrasonic wash in ethanol and acetone step by step, the surface of silicon wafers was observed by AFM sequentially. We have found that the culture leftovers form tight porous networks and a monolayer on the silicon wafers. It is concluded that the leftovers overspreading on the silicon substrates are the base of cell adherence on such smooth inert surfaces.

  8. Evaluation of water based intelligent fluids for resist stripping in single wafer cleaning tools

    Science.gov (United States)

    Rudolph, Matthias; Esche, Silvio; Hohle, Christoph; Schumann, Dirk; Steinke, Philipp; Thrun, Xaver; von Sonntag, Justus

    2016-03-01

    The application of phasefluid based intelligent fluids® in the field of photoresist stripping was studied. Due to their highly dynamic inner structure, phasefluids penetrate into the polymer network of photoresists and small gaps between resist layer and substrate and lift off the material from the surface. These non-aggressive stripping fluids were investigated regarding their efficiency in various resist stripping applications including initial results on copper metallization. Furthermore intelligent fluids® have been evaluated on an industry standard high volume single wafer cleaner. A baseline process on 300 mm wafers has been developed and characterized in terms of metallic and ionic impurities and defect level. Finally a general proof of concept for removal of positive tone resist from 300 mm silicon wafers is demonstrated.

  9. Vertically Conductive Single-Crystal SiC-Based Bragg Reflector Grown on Si Wafer

    Science.gov (United States)

    Massoubre, David; Wang, Li; Hold, Leonie; Fernandes, Alanna; Chai, Jessica; Dimitrijev, Sima; Iacopi, Alan

    2015-11-01

    Single-crystal silicon carbide (SiC) thin-films on silicon (Si) were used for the fabrication and characterization of electrically conductive distributed Bragg reflectors (DBRs) on 100 mm Si wafers. The DBRs, each composed of 3 alternating layers of SiC and Al(Ga)N grown on Si substrates, show high wafer uniformity with a typical maximum reflectance of 54% in the blue spectrum and a stopband (at 80% maximum reflectance) as large as 100 nm. Furthermore, high vertical electrical conduction is also demonstrated resulting to a density of current exceeding 70 A/cm2 above 1.5 V. Such SiC/III-N DBRs with high thermal and electrical conductivities could be used as pseudo-substrate to enhance the efficiency of SiC-based and GaN-based optoelectronic devices on large Si wafers.

  10. Adhesion of neural cells on silicon wafer with nano-topographic surface

    Science.gov (United States)

    Fan, Y. W.; Cui, F. Z.; Chen, L. N.; Zhai, Y.; Xu, Q. Y.; Lee, I.-S.

    2002-02-01

    The adherence and subsequent viability of central neural cells (substantia nigra) on silicon wafers with different surface roughness conditions were investigated. Various roughness conditions of the silicon wafer were achieved by etching at different times. The topography was evaluated by AFM. Primary neurons were obtained from Wistar rats. The adherence and subsequent viability of the cells on the wafer were examined by scanning electronic microscopy and fluorescence immunostaining of tyrosine hydroxylase. It is found that the surface roughness affects significantly cell adhesion and viability. Cells can survive for over 5 days on the surface with average roughness in the range 20-70 nm. Such a treatment may provide a new method to make a mild interface of silicon-based electronic devices and neurons as well as other living tissues.

  11. Electrical characterization of thin SOI wafers using lateral MOS transient capacitance measurements

    International Nuclear Information System (INIS)

    Wang, D.; Ueda, A.; Takada, H.; Nakashima, H.

    2006-01-01

    A novel electrical evaluation method was proposed for crystal quality characterization of thin Si on insulator (SOI) wafers, which was done by measurement of minority carrier generation lifetime (τ g ) using transient capacitance method for lateral metal-oxide-semiconductor (MOS) capacitor. The lateral MOS capacitors were fabricated on three kinds of thin SOI wafers. The crystal quality difference among these three wafers was clearly shown by the τ g measurement results and discussed from a viewpoint of SOI fabrication. The series resistance influence on the capacitance measurement for this lateral MOS capacitor was discussed in detail. The validity of this method was confirmed by comparing the intensities of photoluminescence signals due to electron-hole droplet in the band-edge emission

  12. Development of ultra-low impedance Through-wafer Micro-vias

    Energy Technology Data Exchange (ETDEWEB)

    Finkbeiner, F.M. E-mail: fmf@lheapop.gsfc.nasa.gov; Adams, C.; Apodaca, E.; Chervenak, J.A.; Fischer, J.; Doan, N.; Li, M.J.; Stahle, C.K.; Brekosky, R.P.; Bandler, S.R.; Figueroa-Feliciano, E.; Lindeman, M.A.; Kelley, R.L.; Saab, T.; Talley, D.J

    2004-03-11

    Concurrent with our microcalorimeter array fabrication for Constellation-X technology development, we are developing ultra-low impedance Through-Wafer Micro-Vias (TWMV) as electrical interconnects for superconducting circuits. The TWMV will enable the electrical contacts of each detector to be routed to contacts on the backside of the array. There, they can be bump-bonded to a wiring fan-out board which interfaces with the front-end Superconducting Quantum Interference Device readout. We are concentrating our developmental efforts on ultra-low impedance copper and superconducting aluminum TWMV in 300-400 micron thick silicon wafers. For both schemes, a periodic pulse-reverse electroplating process is used to fill or coat micron-scale through-wafer holes of aspect ratios up to 20. Here we discuss the design, fabrication process, and recent electro-mechanical test results of Al and Cu TWMV at room and cryogenic temperatures.

  13. Terahertz transmission properties of silicon wafers using continuous-wave terahertz spectroscopy

    International Nuclear Information System (INIS)

    Kim, Chihoon; Ahn, Jae Sung; Eom, Joo Beom; Ji, Taeksoo

    2017-01-01

    We present the spectral properties of Si wafers using continuous-wave terahertz (CW-THz) spectroscopy. By using a tunable laser source and a fixed distributed-feedback laser diode (DFB-LD), a stably tunable beat source for CW-THz spectroscopy system can be implemented. THz radiation is generated in the frequency range of 100 GHz–800 GHz by photomixing in a photoconductive antenna. We also measured CW-THz waveforms by changing the beat frequency and confirmed repeatability through repeated measurement. We calculated the peaks of the THz frequency by taking fast Fourier transforms (FFTs) of measured THz waveforms. The feasibility of CW-THz spectroscopy is demonstrated by the THz spectra of Si wafers with different resistivities, mobilities, and carrier concentrations. The results show that Si wafers with a lower resistivity absorb more THz waves. Thus, we expect our CW-THz system to have the advantage of being able to perform fast non-destructive analysis. (paper)

  14. Murine Ileocolic Bowel Resection with Primary Anastomosis

    Science.gov (United States)

    Perry, Troy; Borowiec, Anna; Dicken, Bryan; Fedorak, Richard; Madsen, Karen

    2014-01-01

    Intestinal resections are frequently required for treatment of diseases involving the gastrointestinal tract, with Crohn’s disease and colon cancer being two common examples. Despite the frequency of these procedures, a significant knowledge gap remains in describing the inherent effects of intestinal resection on host physiology and disease pathophysiology. This article provides detailed instructions for an ileocolic resection with primary end-to-end anastomosis in mice, as well as essential aspects of peri-operative care to maximize post-operative success. When followed closely, this procedure yields a 95% long-term survival rate, no failure to thrive, and minimizes post-operative complications of bowel obstruction and anastomotic leak. The technical challenges of performing the procedure in mice are a barrier to its wide spread use in research. The skills described in this article can be acquired without previous surgical experience. Once mastered, the murine ileocolic resection procedure will provide a reproducible tool for studying the effects of intestinal resection in models of human disease. PMID:25406841

  15. Vertebral Column Resection for Rigid Spinal Deformity.

    Science.gov (United States)

    Saifi, Comron; Laratta, Joseph L; Petridis, Petros; Shillingford, Jamal N; Lehman, Ronald A; Lenke, Lawrence G

    2017-05-01

    Broad narrative review. To review the evolution, operative technique, outcomes, and complications associated with posterior vertebral column resection. A literature review of posterior vertebral column resection was performed. The authors' surgical technique is outlined in detail. The authors' experience and the literature regarding vertebral column resection are discussed at length. Treatment of severe, rigid coronal and/or sagittal malalignment with posterior vertebral column resection results in approximately 50-70% correction depending on the type of deformity. Surgical site infection rates range from 2.9% to 9.7%. Transient and permanent neurologic injury rates range from 0% to 13.8% and 0% to 6.3%, respectively. Although there are significant variations in EBL throughout the literature, it can be minimized by utilizing tranexamic acid intraoperatively. The ability to correct a rigid deformity in the spine relies on osteotomies. Each osteotomy is associated with a particular magnitude of correction at a single level. Posterior vertebral column resection is the most powerful posterior osteotomy method providing a successful correction of fixed complex deformities. Despite meticulous surgical technique and precision, this robust osteotomy technique can be associated with significant morbidity even in the most experienced hands.

  16. Introduction of high oxygen concentrations into silicon wafers by high-temperature diffusion

    CERN Document Server

    Casse, G L; Lemeilleur, F; Ruzin, A; Wegrzecki, M

    1999-01-01

    The tolerance of silicon detectors to hadron irradiation can be improved by the introduction of a high concentration of oxygen into the starting material. High-resistivity Floating-Zone (FZ) silicon is required for detectors used in particle physics applications. A significantly high oxygen concentration (>10/sup 17/ atoms cm/sup -3 /) cannot readily be achieved during the FZ silicon refinement. The diffusion of oxygen at elevated temperatures from a SiO/sub 2/ layer grown on both sides of a silicon wafer is a simple and effective technique to achieve high and uniform concentrations of oxygen throughout the bulk of a 300 mu m thick silicon wafer. (7 refs).

  17. Nano silver-catalyzed chemical etching of polycrystalline silicon wafer for solar cell application

    Directory of Open Access Journals (Sweden)

    S. R. Chen

    2016-03-01

    Full Text Available Silver nanoparticles were deposited on the surface of polycrystalline silicon wafer via vacuum thermal evaporation and metal-catalyzed chemical etching (MCCE was conducted in a HF-H2O2 etching system. Treatment of the etched silicon wafer with HF transformed the textured structure on the surface from nanorods into nanocones. An etching time of 30 s and treatment with HF resulted in nanocones with uniform size distribution and a reflectivity as low as 1.98% across a spectral range from 300 to 1000 nm.

  18. Micropore x-ray optics using anisotropic wet etching of (110) silicon wafers

    International Nuclear Information System (INIS)

    Ezoe, Yuichiro; Koshiishi, Masaki; Mita, Makoto; Mitsuda, Kazuhisa; Hoshino, Akio; Ishisaki, Yoshitaka; Yang Zhen; Takano, Takayuki; Maeda, Ryutaro

    2006-01-01

    To develop x-ray mirrors for micropore optics, smooth silicon (111)sidewalls obtained after anisotropic wet etching of a silicon (110) wafer were studied. A sample device with 19 μm wide (111) sidewalls was fabricated using a 220 μm thick silicon (110) wafer and potassium hydroxide solution. For what we believe to be the first time,x-ray reflection on the (111) sidewalls was detected in the angular response measurement. Compared to ray-tracing simulations, the surface roughness of the sidewalls was estimated to be 3-5 nm, which is consistent with the atomic force microscope and the surface profiler measurements

  19. Split-Capacitance and Conductance-Frequency Characteristics of SOI Wafers in Pseudo-MOSFET Configuration

    KAUST Repository

    Pirro, Luca

    2015-09-01

    Recent experimental results have demonstrated the possibility of characterizing silicon-on-insulator (SOI) wafers through split C-V measurements in the pseudo-MOSFET configuration. This paper analyzes the capacitance and conductance versus frequency characteristics. We discuss the conditions under which it is possible to extract interface trap density in bare SOI wafers. The results indicate, through both measurements and simulations, that the signature due to interface trap density is present in small-area samples, but is masked by the RC response of the channel in regular, large-area ones, making the extraction in standard samples problematic. © 1963-2012 IEEE.

  20. First thin AC-coupled silicon strip sensors on 8-inch wafers

    Energy Technology Data Exchange (ETDEWEB)

    Bergauer, T., E-mail: thomas.bergauer@oeaw.ac.at [Institute of High Energy Physics of the Austrian Academy of Sciences, Nikolsdorfer Gasse 18, 1050 Wien (Vienna) (Austria); Dragicevic, M.; König, A. [Institute of High Energy Physics of the Austrian Academy of Sciences, Nikolsdorfer Gasse 18, 1050 Wien (Vienna) (Austria); Hacker, J.; Bartl, U. [Infineon Technologies Austria AG, Siemensstrasse 2, 9500 Villach (Austria)

    2016-09-11

    The Institute of High Energy Physics (HEPHY) in Vienna and the semiconductor manufacturer Infineon Technologies Austria AG developed a production process for planar AC-coupled silicon strip sensors manufactured on 200 μm thick 8-inch p-type wafers. In late 2015, the first wafers were delivered featuring the world's largest AC-coupled silicon strip sensors. Detailed electrical measurements were carried out at HEPHY, where single strip and global parameters were measured. Mechanical studies were conducted and the long-term behavior was investigated using a climate chamber. Furthermore, the electrical properties of various test structures were investigated to validate the quality of the manufacturing process.

  1. Performance of a novel wafer scale CMOS active pixel sensor for bio-medical imaging

    International Nuclear Information System (INIS)

    Esposito, M; Evans, P M; Wells, K; Anaxagoras, T; Konstantinidis, A C; Zheng, Y; Speller, R D; Allinson, N M

    2014-01-01

    Recently CMOS active pixels sensors (APSs) have become a valuable alternative to amorphous silicon and selenium flat panel imagers (FPIs) in bio-medical imaging applications. CMOS APSs can now be scaled up to the standard 20 cm diameter wafer size by means of a reticle stitching block process. However, despite wafer scale CMOS APS being monolithic, sources of non-uniformity of response and regional variations can persist representing a significant challenge for wafer scale sensor response. Non-uniformity of stitched sensors can arise from a number of factors related to the manufacturing process, including variation of amplification, variation between readout components, wafer defects and process variations across the wafer due to manufacturing processes. This paper reports on an investigation into the spatial non-uniformity and regional variations of a wafer scale stitched CMOS APS. For the first time a per-pixel analysis of the electro-optical performance of a wafer CMOS APS is presented, to address inhomogeneity issues arising from the stitching techniques used to manufacture wafer scale sensors. A complete model of the signal generation in the pixel array has been provided and proved capable of accounting for noise and gain variations across the pixel array. This novel analysis leads to readout noise and conversion gain being evaluated at pixel level, stitching block level and in regions of interest, resulting in a coefficient of variation ⩽1.9%. The uniformity of the image quality performance has been further investigated in a typical x-ray application, i.e. mammography, showing a uniformity in terms of CNR among the highest when compared with mammography detectors commonly used in clinical practice. Finally, in order to compare the detection capability of this novel APS with the technology currently used (i.e. FPIs), theoretical evaluation of the detection quantum efficiency (DQE) at zero-frequency has been performed, resulting in a higher DQE for this

  2. Performance of a novel wafer scale CMOS active pixel sensor for bio-medical imaging.

    Science.gov (United States)

    Esposito, M; Anaxagoras, T; Konstantinidis, A C; Zheng, Y; Speller, R D; Evans, P M; Allinson, N M; Wells, K

    2014-07-07

    Recently CMOS active pixels sensors (APSs) have become a valuable alternative to amorphous silicon and selenium flat panel imagers (FPIs) in bio-medical imaging applications. CMOS APSs can now be scaled up to the standard 20 cm diameter wafer size by means of a reticle stitching block process. However, despite wafer scale CMOS APS being monolithic, sources of non-uniformity of response and regional variations can persist representing a significant challenge for wafer scale sensor response. Non-uniformity of stitched sensors can arise from a number of factors related to the manufacturing process, including variation of amplification, variation between readout components, wafer defects and process variations across the wafer due to manufacturing processes. This paper reports on an investigation into the spatial non-uniformity and regional variations of a wafer scale stitched CMOS APS. For the first time a per-pixel analysis of the electro-optical performance of a wafer CMOS APS is presented, to address inhomogeneity issues arising from the stitching techniques used to manufacture wafer scale sensors. A complete model of the signal generation in the pixel array has been provided and proved capable of accounting for noise and gain variations across the pixel array. This novel analysis leads to readout noise and conversion gain being evaluated at pixel level, stitching block level and in regions of interest, resulting in a coefficient of variation ⩽1.9%. The uniformity of the image quality performance has been further investigated in a typical x-ray application, i.e. mammography, showing a uniformity in terms of CNR among the highest when compared with mammography detectors commonly used in clinical practice. Finally, in order to compare the detection capability of this novel APS with the technology currently used (i.e. FPIs), theoretical evaluation of the detection quantum efficiency (DQE) at zero-frequency has been performed, resulting in a higher DQE for this

  3. Probing and irradiation tests of ALICE pixel chip wafers and sensors

    CERN Document Server

    Cinausero, M; Antinori, F; Chochula, P; Dinapoli, R; Dima, R; Fabris, D; Galet, G; Lunardon, M; Manea, C; Marchini, S; Martini, S; Moretto, S; Pepato, Adriano; Prete, G; Riedler, P; Scarlassara, F; Segato, G F; Soramel, F; Stefanini, G; Turrisi, R; Vannucci, L; Viesti, G

    2004-01-01

    In the framework of the ALICE Silicon Pixel Detector (SPD) project a system dedicated to the tests of the ALICE1LHCb chip wafers has been assembled and is now in use for the selection of pixel chips to be bump-bonded to sensor ladders. In parallel, radiation hardness tests of the SPD silicon sensors have been carried out using the 27 MeV proton beam delivered by the XTU TANDEM accelerator at the SIRAD facility in LNL. In this paper we describe the wafer probing and irradiation set-ups and we report the obtained results. (6 refs).

  4. Bismuth onion thin film in situ grown on silicon wafer synthesized through a hydrothermal approach

    International Nuclear Information System (INIS)

    Zhao Yue; Liu Hong; Liu Jin; Hu Chenguo; Wang Jiyang

    2010-01-01

    Bismuth onion structured nanospheres with the same structure as carbon onions have been synthesized and observed. The nanospheres were synthesized through a hydrothermal method using bismuth hydroxide and silicon wafer as reactants. By controlling the heating temperature, heating time, and the pressure, nanoscale bismuth spheres can be in situ synthesized on silicon wafer, and forms a bismuth onion film on the substrate. The electronic property of the films was investigated. A formation mechanism of the formation of bismuth onions and the onion film has been proposed on the basis of experimental observations.

  5. Robot-assisted Resection of Paraspinal Schwannoma

    Science.gov (United States)

    Yang, Moon Sool; Kim, Keung Nyun; Yoon, Do Heum; Pennant, William

    2011-01-01

    Resection of retroperitoneal tumors is usually perfomed using the anterior retroperitoneal approach. Our report presents an innovative method utilizing a robotic surgical system. A 50-yr-old male patient visited our hospital due to a known paravertebral mass. Magnetic resonance imaging showed a well-encapsulated mass slightly abutting the abdominal aorta and left psoas muscle at the L4-L5 level. The tumor seemed to be originated from the prevertebral sympathetic plexus or lumbosacral trunk and contained traversing vessels around the tumor capsule. A full-time robotic transperitoneal tumor resection was performed. Three trocars were used for the robotic camera and working arms. The da Vinci Surgical System® provided delicate dissection in the small space and the tumor was completely removed without damage to the surrounding organs and great vessels. This case demonstrates the feasibility of robotic resection in retroperitoneal space. Robotic surgery offered less invasiveness in contrast to conventional open surgery. PMID:21218046

  6. Neurologic deficit after resection of the sacrum.

    Science.gov (United States)

    Biagini, R; Ruggieri, P; Mercuri, M; Capanna, R; Briccoli, A; Perin, S; Orsini, U; Demitri, S; Arlecchini, S

    1997-01-01

    The authors describe neurologic deficit (sensory, motor, and sphincteral) resulting from sacrifice of the sacral nerve roots removed during resection of the sacrum. The anatomical and functional bases of sphincteral continence and the amount of neurologic deficit are discussed based on level of sacral resection. A large review of the literature on the subject is reported and discussed. The authors emphasize how the neurophysiological bases of sphincteral continence (rectum and bladder) and of sexual ability are still not well known, and how the literature reveals disagreement on the subject. A score system is proposed to evaluate neurologic deficit. The clinical model of neurologic deficit caused by resection of the sacrum may be extended to an evaluation of post-traumatic deficit.

  7. Hepatic resection and regeneration. Past and present

    International Nuclear Information System (INIS)

    Hatsuse, Kazuo

    2007-01-01

    Hepatic surgery has been performed on condition that the liver regenerates after hepatic resection, and the development of liver anatomy due to Glisson, Rex, and Couinaud has thrown light on hepatic surgery Understanding of feeding and drainage vessels became feasible for systemic hepatic resection; however, it seems to have been the most important problem to control the bleeding during hepatic resection. New types of devices such as cavitron ultrasonic surgical aspirator (CUSA) and Microwave coagulation were exploited to control blood loss during hepatic surgery. Pringle maneuver for exclusion feeding vessels of the liver and the decrease of central venous pressure during anesthesia enabled further decrease of blood loss. Nowadays, 3D-CT imaging may depict feeding and drainage vessels in relation to liver mass, and surgeons can simulate hepatic surgery in virtual reality before surgery, allowing hepatectomy to be performed without blood transfusion. Thus, hepatic resection has been a safe procedure, but there's been a significant research on how much of the liver can be resected without hepatic failure. A prediction scoring system based on ICGR15, resection rates, and age is mostly reliable in some criteria. Even if hepatectomy is performed with a good prediction score, the massive bleeding and associated infection may induce postoperative hepatic failure, while the criteria of postoperative hepatic failure have not yet established. Hepatic failure is supposed to be induced by the apoptosis of mature hepatocytes and necrosis originated from microcirculation disturbance of the liver. Prostaglandin E1 for the improvement of microcirculation, steroid for the inhibition of cytokines inducing apoptosis, and blood purification to exclude cytokines have been tried separately or concomitantly. New therapeutic approaches, especially hepatic regeneration from the stem cell, are expected. (author)

  8. Multi-wafer growth of highly uniform InGaP/GaAs by low pressure MOVPE

    Science.gov (United States)

    McKee, M. A.; McGivney, T.; Walker, D.; Capuder, K.; Norris, P. E.; Stall, R. A.; Rose, B. C.

    1992-03-01

    This paper reports on the large area growth of InGaP/GaAs heterostructures for short wavelength applications (λ ˜ 650 nm) by low pressure MOVPE in a vertical, high speed, rotating disk reactor. Highly uniform films were obtained both on a single 50 mm diam wafer at the center of a 5 inch diam wafer platter and on three, 50 mm diameter GaAs wafers symmetrically placed on a 5 inch diam platter. Characterization was performed by x-ray diffraction, SEM, and room temperature photoluminescence (PL) mapping. For the single wafer growth, PL mapping results show that the total range on wavelength was ±2 nm with a 2 mm edge exclusion. The standard deviation of the peak wavelength, σ w , is 0.7 nm. Thickness uniformity, measured by SEM, is less than 2%. Similar results were obtained for the multi-wafer runs. Each individual wafer has a σ w of 1.1 nm. The wafers have nearly identical PL maps with the variation of the average wavelength from the three wafers within ±0.1 nm.

  9. Characterization of energy use in 300 mm DRAM (Dynamic Random Access Memory) wafer fabrication plants (fabs) in Taiwan

    International Nuclear Information System (INIS)

    Hu, Shih-Cheng; Xu, Tengfang; Chaung, Tony; Chan, David Y.-L.

    2010-01-01

    Driven by technology advances and demand for enhanced productivity, migration of wafer fabrication for DRAM (Dynamic Random Access Memory) toward increased wafer size has become the fast-growing trend in semiconductor industry. Taiwan accounts for about 18% of the total DRAM wafer production in the world. The energy use required for operating wafer fabrication plants (fabs) is intensive and has become one of the major concerns to production power reliability in the island. This paper characterizes the energy use in four 300 mm DRAM wafer fabs in Taiwan through performing surveys and on-site measurements. Specifically, the objectives of this study are to characterize the electric energy consumption and production of 300 mm DRAM fabs by using various performance metrics, including PEI ((production efficiency index), annual electric power consumption normalized by annual produced wafer area) and EUI ((electrical utilization index), annual electric power consumption normalized by UOP (units of production), which is defined as the product of annual produced wafer area and the average number of mask layers of a wafer). The results show that the PEI and EUI values are 0.743 kWh/cm 2 and 0.0272 kWh/UOP, respectively. Using EUI in assessing energy efficiency of the fab production provides more consistent comparisons than using PEI alone.

  10. Anesthesia for tracheal resection and reconstruction.

    Science.gov (United States)

    Hobai, Ion A; Chhangani, Sanjeev V; Alfille, Paul H

    2012-12-01

    Tracheal resection and reconstruction (TRR) is the treatment of choice for most patients with tracheal stenosis or tracheal tumors. Anesthesia for TRR offers distinct challenges, especially for the less experienced practitioner. This article explores the preoperative assessment, strategies for induction and emergence from anesthesia, the essential coordination between the surgical and anesthesia teams during airway excision and anastomosis, and postoperative care. The most common complications are reviewed. Targeted readership is practitioners with less extensive experience in managing airway surgery cases. As such, the article focuses first on the most common proximal tracheal resection. Final sections discuss specific considerations for more complicated cases. Copyright © 2012 Elsevier Inc. All rights reserved.

  11. [Laparoscopic resection of stomach in case of stomach ulcer].

    Science.gov (United States)

    Sazhin, I V; Sazhin, V P; Nuzhdikhin, A V

    2014-01-01

    Laparoscopic resection of stomach was done in 84 patients with complicated peptic ulcer of stomach and duodenum. There were 1.2% post-operative complications in case of laparoscopic resection of stomach in comparison with open resection, which had 33.3% complications. There were not deaths in case of laparoscopic resection of stomach. This indication was about 4% in patients after open resection. It was determined that functionalefficiency afterlaparoscopic resection was in 1.6-1.8 times higher than afteropen resectionof stomach.

  12. Improvement of the thickness distribution of a quartz crystal wafer by numerically controlled plasma chemical vaporization machining

    International Nuclear Information System (INIS)

    Shibahara, Masafumi; Yamamura, Kazuya; Sano, Yasuhisa; Sugiyama, Tsuyoshi; Endo, Katsuyoshi; Mori, Yuzo

    2005-01-01

    To improve the thickness uniformity of thin quartz crystal wafer, a new machining process that utilizes an atmospheric pressure plasma was developed. In an atmospheric pressure plasma process, since the kinetic energy of ions that impinge to the wafer surface is small and the density of the reactive species is large, high-efficiency machining without damage is realized, and the thickness distribution is corrected by numerically controlled scanning of the quartz wafer to the localized high-density plasma. By using our developed machining process, the thickness distribution of an AT cut wafer was improved from 174 nm [peak to valley (p-v)] to 67 nm (p-v) within 94 s. Since there are no unwanted spurious modes in the machined quartz wafer, it was proved that the developed machining method has a high machining efficiency without any damage

  13. Investigation of optical properties of benzocyclobutene wafer bonding layer used for 3D interconnects via infrared spectroscopic ellipsometry

    International Nuclear Information System (INIS)

    Kamineni, Vimal K.; Singh, Pratibha; Kong, LayWai; Hudnall, John; Qureshi, Jamal; Taylor, Chris; Rudack, Andy; Arkalgud, Sitaram; Diebold, Alain C.

    2011-01-01

    Benzocyclobutene (BCB) used for bonding silicon wafers to enable 3D interconnect technology is characterized using spectroscopic ellipsometry (SE). SE is a non-destructive technique that has been used to characterize the thickness and dielectric properties of BCB. The infrared (IR) absorption spectrum was used to calculate the percentage of curing of BCB on 300 mm bare and bonded wafers. The percentage of curing in BCB is a key parameter that impacts the bond strength and bond quality. This study presents the potential application of IRSE for measurements on bonded wafers to characterize the chemical information, curing percentage, bond quality and thickness of the BCB bonding layer. One of the key issues in the process development and characterization of BCB bonding for 3D interconnects of 300 mm wafers is the presence of dendrites and voids between the bonded wafers. The presence of dendrites and voids was identified by using scanning acoustic microscopy (SAM) and imaged by scanning electron microscope (SEM).

  14. Investigation of optical properties of benzocyclobutene wafer bonding layer used for 3D interconnects via infrared spectroscopic ellipsometry

    Energy Technology Data Exchange (ETDEWEB)

    Kamineni, Vimal K., E-mail: vkamineni@uamail.albany.ed [College of Nanoscale Science and Engineering, University at Albany, Albany, NY 12203 (United States); Singh, Pratibha [GLOBALFOUNDRIES Inc., Albany, NY 12203 (United States); SEMATECH, Albany, NY 12203 (United States); Kong, LayWai [College of Nanoscale Science and Engineering, University at Albany, Albany, NY 12203 (United States); Hudnall, John [SEMATECH, Albany, NY 12203 (United States); Qureshi, Jamal [College of Nanoscale Science and Engineering, University at Albany, Albany, NY 12203 (United States); SEMATECH, Albany, NY 12203 (United States); Taylor, Chris [SEMATECH, Albany, NY 12203 (United States); Hewlett-Packard Company, Corvallis, OR (United States); Rudack, Andy; Arkalgud, Sitaram [SEMATECH, Albany, NY 12203 (United States); Diebold, Alain C. [College of Nanoscale Science and Engineering, University at Albany, Albany, NY 12203 (United States)

    2011-02-28

    Benzocyclobutene (BCB) used for bonding silicon wafers to enable 3D interconnect technology is characterized using spectroscopic ellipsometry (SE). SE is a non-destructive technique that has been used to characterize the thickness and dielectric properties of BCB. The infrared (IR) absorption spectrum was used to calculate the percentage of curing of BCB on 300 mm bare and bonded wafers. The percentage of curing in BCB is a key parameter that impacts the bond strength and bond quality. This study presents the potential application of IRSE for measurements on bonded wafers to characterize the chemical information, curing percentage, bond quality and thickness of the BCB bonding layer. One of the key issues in the process development and characterization of BCB bonding for 3D interconnects of 300 mm wafers is the presence of dendrites and voids between the bonded wafers. The presence of dendrites and voids was identified by using scanning acoustic microscopy (SAM) and imaged by scanning electron microscope (SEM).

  15. A facility for plastic deformation of germanium single-crystal wafers

    DEFF Research Database (Denmark)

    Lebech, B.; Theodor, K.; Breiting, B.

    1998-01-01

    . All movements and temperature changes are done by a robot via a PLC-control system. Two nine-crystal focusing monochromators (54 x 116 and 70 x 116 mm(2)) made from 100 wafers with average mosaicity similar to 13' have been constructed. Summaries of the test results are presented. (C) 1998 Elsevier...

  16. Fabrication of through-wafer 3D microfluidics in silicon carbide using femtosecond laser

    Science.gov (United States)

    Huang, Yinggang; Wu, Xiudong; Liu, Hewei; Jiang, Hongrui

    2017-06-01

    We demonstrate a prototype through-wafer microfluidic structure in bulk silicon carbide (SiC) fabricated by femtosecond laser micromachining. The effects of laser fluence and scanning speed on the laser-affected zone are also investigated. Furthermore, the wettability of the laser-affected surface for the target liquid, mineral oil, is examined. Microchannels of various cross-sectional shapes are fabricated by the femtosecond laser and their effects on the liquid flow are simulated and compared. This fabrication approach offers a fast and efficient route to implement SiC-based through-wafer micro-structures, which are not able to be realized using other methods such as chemical etching. The flexibility of manufacturing 3D structures based on this fabrication method enables more complex structures as well. Smooth liquid flow in the microchannels of the bulk SiC substrate is presented. The work shown here paves a new way for various applications such as reliable microfluidic systems in a high-temperature, high radioactivity, and corrosive environment, and could be combined with SiC wafer-to-wafer bonding to realize a plethora of novel microelectromechanical (MEMS) structures.

  17. Crystallographic Orientation Identification in Multicrystalline Silicon Wafers Using NIR Transmission Intensity

    Science.gov (United States)

    Skenes, Kevin; Kumar, Arkadeep; Prasath, R. G. R.; Danyluk, Steven

    2018-02-01

    Near-infrared (NIR) polariscopy is a technique used for the non-destructive evaluation of the in-plane stresses in photovoltaic silicon wafers. Accurate evaluation of these stresses requires correct identification of the stress-optic coefficient, a material property which relates photoelastic parameters to physical stresses. The material stress-optic coefficient of silicon varies with crystallographic orientation. This variation poses a unique problem when measuring stresses in multicrystalline silicon (mc-Si) wafers. This paper concludes that the crystallographic orientation of silicon can be estimated by measuring the transmission of NIR light through the material. The transmission of NIR light through monocrystalline wafers of known orientation were compared with the transmission of NIR light through various grains in mc-Si wafers. X-ray diffraction was then used to verify the relationship by obtaining the crystallographic orientations of these assorted mc-Si grains. Variation of transmission intensity for different crystallographic orientations is further explained by using planar atomic density. The relationship between transmission intensity and planar atomic density appears to be linear.

  18. Wafer level reliability monitoring strategy of an advanced multi-process CMOS foundry

    NARCIS (Netherlands)

    Scarpa, Andrea; Tao, Guoqiao; Kuper, F.G.

    2000-01-01

    In an advanced multi-process CMOS foundry it is strategically important to make use of an optimum reliability monitoring strategy, in order to be able to run well controlled processes. Philips Semiconductors Business Unit Foundries wafer fab MOS4YOU has developed an end-of-line ultra-fast

  19. Light coupling and light trapping in alkaline etched multicrystalline silicon wafers for solar cells

    NARCIS (Netherlands)

    Hylton, J.D.

    2006-01-01

    The reflection reducing and light trapping properties of alkaline etched multicrystalline silicon wafers are investigated experimentally. Following an overview of various chemical texturisation methods and their effect upon the surface morphology, a high concentration saw-damage etch and a low

  20. Wafer scale nano-membrane supported on a silicon microsieve using thin-film transfer technology

    NARCIS (Netherlands)

    Unnikrishnan, S.; Jansen, Henricus V.; Berenschot, Johan W.; Elwenspoek, Michael Curt

    A new micromachining method to fabricate wafer scale nano-membranes is described. The delicate thin-film nano-membrane is supported on a robust silicon microsieve fabricated by plasma etching. The silicon sieve is micromachined independently of the thin-film, which is later transferred onto it by

  1. A new cleaning process for the metallic contaminants on a post-CMP wafer's surface

    International Nuclear Information System (INIS)

    Gao Baohong; Liu Yuling; Wang Chenwei; Wang Shengli; Zhou Qiang; Tan Baimei; Zhu Yadong

    2010-01-01

    This paper presents a new cleaning process using boron-doped diamond (BDD) film anode electrochemical oxidation for metallic contaminants on polished silicon wafer surfaces. The BDD film anode electrochemical oxidation can efficiently prepare pyrophosphate peroxide, pyrophosphate peroxide can oxidize organic contaminants, and pyrophosphate peroxide is deoxidized into pyrophosphate. Pyrophosphate, a good complexing agent, can form a metal complex, which is a structure consisting of a copper ion, bonded to a surrounding array of two pyrophosphate anions. Three polished wafers were immersed in the 0.01 mol/L CuSO 4 solution for 2 h in order to make comparative experiments. The first one was cleaned by pyrophosphate peroxide, the second by RCA (Radio Corporation of America) cleaning, and the third by deionized (DI) water. The XPS measurement result shows that the metallic contaminants on wafers cleaned by the RCA method and by pyrophosphate peroxide is less than the XPS detection limits of 1 ppm. And the wafer's surface cleaned by pyrophosphate peroxide is more efficient in removing organic carbon residues than RCA cleaning. Therefore, BDD film anode electrochemical oxidation can be used for microelectronics cleaning, and it can effectively remove organic contaminants and metallic contaminants in one step. It also achieves energy saving and environmental protection. (semiconductor technology)

  2. Low temperature fusion wafer bonding quality investigation for failure mode analysis

    NARCIS (Netherlands)

    Dragoi, V.; Czurratis, P.; Brand, S.; Beyersdorfer, J.; Patzig, C.; Krugers, J.P.; Schrank, F.; Siegert, J.; Petzold, M.

    2012-01-01

    In this paper, a brief summary of potential defect formation and failure characteristics for low temperature plasma-assisted Si wafer bonding in correlation to different influencing factors is given. In terms of a failure catalogue classification, these defects are related to incoming material

  3. Design Expert Supported Mathematical Optimization and Predictability Study of Buccoadhesive Pharmaceutical Wafers of Loratadine

    Science.gov (United States)

    Dey, Surajit; Parcha, Versha; Bhattacharya, Shiv Sankar; Ghosh, Amitava

    2013-01-01

    Objective. The objective of this work encompasses the application of the response surface approach in the development of buccoadhesive pharmaceutical wafers of Loratadine (LOR). Methods. Experiments were performed according to a 32 factorial design to evaluate the effects of buccoadhesive polymer, sodium alginate (A), and lactose monohydrate as ingredient, of hydrophilic matrix former (B) on the bioadhesive force, disintegration time, percent (%) swelling index, and time taken for 70% drug release (t 70%). The effect of the two independent variables on the response variables was studied by response surface plots and contour plots generated by the Design-Expert software. The desirability function was used to optimize the response variables. Results. The compatibility between LOR and the wafer excipients was confirmed by differential scanning calorimetry, FTIR spectroscopy, and X-ray diffraction (XRD) analysis. Bioadhesion force, measured with TAXT2i texture analyzer, showed that the wafers had a good bioadhesive property which could be advantageous for retaining the drug into the buccal cavity. Conclusion. The observed responses taken were in agreement with the experimental values, and Loratadine wafers were produced with less experimental trials, and a patient compliant product was achieved with the concept of formulation by design. PMID:23781498

  4. Wafer-Scale Leaning Silver Nanopillars for Molecular Detection at Ultra-Low Concentrations

    DEFF Research Database (Denmark)

    Wu, Kaiyu; Rindzevicius, Tomas; Schmidt, Michael Stenbæk

    2015-01-01

    Wafer-scale surface-enhanced Raman scattering (SERS) substrates fabricated using maskless lithography are important for scalable production targets. Large-area, leaning silver-capped silicon nanopillar (Ag NP) structures suitable for SERS molecular detection at extremely low analyte concentrations...

  5. Material size effects on crack growth along patterned wafer-level Cu–Cu bonds

    DEFF Research Database (Denmark)

    Tvergaard, Viggo; Niordson, Christian Frithiof; Hutchinson, John W.

    2013-01-01

    The role of micron-scale patterning on the interface toughness of bonded Cu-to-Cu nanometer-scale films is analyzed, motivated by experimental studies of Tadepalli, Turner and Thompson. In the experiments 400nm Cu films were deposited in various patterns on Si wafer substrates and then bonded...

  6. Graphene-Decorated Nanocomposites for Printable Electrodes in Thin Wafer Devices

    Science.gov (United States)

    Bakhshizadeh, N.; Sivoththaman, S.

    2017-12-01

    Printable electrodes that induce less stress and require lower curing temperatures compared to traditional screen-printed metal pastes are needed in thin wafer devices such as future solar cells, and in flexible electronics. The synthesis of nanocomposites by incorporating graphene nanopowders as well as silver nanowires into epoxy-based electrically conductive adhesives (ECA) is examined to improve electrical conductivity and to develop alternate printable electrode materials that induce less stress on the wafer. For the synthesized graphene and Ag nanowire-decorated ECA nanocomposites, the curing kinetics were studied by dynamic and isothermal differential scanning calorimetry measurements. Thermogravimetric analysis on ECA, ECA-AG and ECA/graphene nanopowder nanocomposites showed that the temperatures for onset of decomposition are higher than their corresponding glass transition temperature ( T g) indicating an excellent thermal resistance. Printed ECA/Ag nanowire nanocomposites showed 90% higher electrical conductivity than ECA films, whereas the ECA/graphene nanocomposites increased the conductivity by over two orders of magnitude. Scanning electron microscopy results also revealed the effect of fillers morphology on the conductivity improvement and current transfer mechanisms in nanocomposites. Residual stress analysis performed on Si wafers showed that the ECA and nanocomposite printed wafers are subjected to much lower stress compared to those printed with metallic pastes. The observed parameters of low curing temperature, good thermal resistance, reasonably high conductivity, and low residual stress in the ECA/graphene nanocomposite makes this material a promising alternative in screen-printed electrode formation in thin substrates.

  7. Wafer-scale fabrication of glass-FEP-glass microfluidic devices for lipid bilayer experiments

    NARCIS (Netherlands)

    Bomer, Johan G.; Prokofyev, A.V.; van den Berg, Albert; le Gac, Severine

    2014-01-01

    We report a wafer-scale fabrication process for the production of glass-FEP-glass microdevices using UV-curable adhesive (NOA81) as gluing material, which is applied using a novel "spin & roll" approach. Devices are characterized for the uniformity of the gluing layer, presence of glue in the

  8. Facile Transferring of Wafer-Scale Ultrathin Alumina Membranes onto Substrates for Nanostructure Patterning.

    Science.gov (United States)

    Al-Haddad, Ahmed; Zhan, Zhibing; Wang, Chengliang; Tarish, Samar; Vellacheria, Ranjith; Lei, Yong

    2015-08-25

    Ordered nanostructure arrays have attracted intensive attention because of their various applications. However, it is still a great challenge to achieve ordered nanostructure patterning over a large area (such as wafer-scale) by a technique that allows high throughput, large pattern area and low equipment costs. Here, through a unique design of the fabrication and transferring processes, we achieve a facile transferring of wafer-scale ultrathin alumina membranes (UTAMs) onto substrates without any twisting, folding, cracking and contamination. The most important in our method is fixing the UTAM onto the wafer-scale substrate before removing the backside Al and alumina barrier layer. It is also demonstrated that the thickness and surface smoothing of UTAMs play crucial roles in this transferring process. By using these perfectly transferred UTAMs as masks, various nanostructure patterning including nanoparticle, nanopore (nanomesh) and nanowire arrays are fabricated on wafer-scale substrates with tunable and uniform dimension. Because there are no requirements for UTAMs, substrates and materials to be deposited, the method presented here shall provide a cost-effective platform for the fabrication of ordered nanostructures on large substrates for various applications in nanotechnology.

  9. Spatially resolved localized vibrational mode spectroscopy of carbon in liquid encapsulated Czochralski grown gallium arsenide wafers

    International Nuclear Information System (INIS)

    Yau, Waifan.

    1988-04-01

    Substitutional carbon on an arsenic lattice site is the shallowest and one of the most dominant acceptors in semi-insulating Liquid Encapsulated Czochralski (LEC) GaAs. However, the role of this acceptor in determining the well known ''W'' shape spatial variation of neutral EL2 concentration along the diameter of a LEC wafer is not known. In this thesis, we attempt to clarify the issue of the carbon acceptor's effect on this ''W'' shaped variation by measuring spatial profiles of this acceptor along the radius of three different as-grown LEC GaAs wafers. With localized vibrational mode absorption spectroscopy, we find that the profile of the carbon acceptor is relatively constant along the radius of each wafer. Average values of concentration are 8 x 10E15 cm -3 , 1.1 x 10E15 cm -3 , and 2.2 x 10E15 cm -3 , respectively. In addition, these carbon acceptor LVM measurements indicate that a residual donor with concentration comparable to carbon exists in these wafers and it is a good candidate for the observed neutral EL2 concentration variation. 22 refs., 39 figs

  10. The preparation and thermoelectric properties of molten salt electrodeposited boron wafers

    International Nuclear Information System (INIS)

    Kumashiro, Y.; Ozaki, S.; Sato, K.; Kataoka, Y.; Hirata, K.; Yokoyama, T.; Nagatani, S.; Kajiyama, K.

    2004-01-01

    We have prepared electrodeposited boron wafer by molten salts with KBF 4 -KF at 680 deg. C using graphite crucible for anode and silicon wafer and nickel plate for cathodes. Experiments were performed by various molar ratios KBF 4 /KF and current densities. Amorphous p-type boron wafers with purity 87% was deposited on nickel plate for 1 h. Thermal diffusivity by ring-flash method and heat capacity by DSC method produced thermal conductivity showing amorphous behavior in the entire temperature range. The systematical results on thermoelectric properties were obtained for the wafers prepared with KBF 4 -KF (66-34 mol%) under various current densities in the range 1-2 A/cm 2 . The temperature dependencies of electrical conductivity showed thermal activated type with activation energy of 0.5 eV. Thermoelectric power tended to increase with increasing temperature up to high temperatures with high values of (1-10) mV/K. Thermoelectric figure-of-merit was 10 -4 /K at high temperatures. Estimated efficiency of thermoelectric energy conversion would be calculated to be 4-5%

  11. Low temperature sacrificial wafer bonding for planarization after very deep etching

    NARCIS (Netherlands)

    Spiering, V.L.; Spiering, V.L.; Berenschot, Johan W.; Elwenspoek, Michael Curt; Fluitman, J.H.J.

    1994-01-01

    A new technique, at temperatures of 150°C or 450°C, that provides planarization after a very deep etching step in silicon is presented. Resist spinning and layer patterning as well as realization of bridges or cantilevers across deep holes becomes possible. The sacrificial wafer bonding technique

  12. Novel SU-8 based vacuum wafer-level packaging for MEMS devices

    DEFF Research Database (Denmark)

    Murillo, Gonzalo; Davis, Zachary James; Keller, Stephan Urs

    2010-01-01

    and versatility. A novel technique of wafer level adhesive bonding, which uses SU-8 as structural and adhesive material, has been developed and successfully demonstrated. Optical inspection and SEM images were used in order to measure the package lid bending and probe the encapsulation sealing. In addition...

  13. Wafer scale lead zirconate titanate film preparation by sol-gel method using stress balance layer

    International Nuclear Information System (INIS)

    Lu Jian; Kobayashi, Takeshi; Yi Zhang; Maeda, Ryutaro; Mihara, Takashi

    2006-01-01

    In this paper, platinum/titanium (Pt/Ti) film was introduced as a residual stress balance layer into wafer scale thick lead zirconate titanate (PZT) film fabrication by sol-gel method. The stress developing in PZT film's bottom electrode as well as in PZT film itself during deposition were analyzed; the wafer curvatures, PZT crystallizations and PZT electric properties before and after using Pt/Ti stress balance layer were studied and compared. It was found that this layer is effective to balance the residual stress in PZT film's bottom electrode induced by thermal expansion coefficient mismatch and Ti diffusion, thus can notably reduce the curvature of 4-in. wafer from - 40.5 μm to - 12.9 μm after PZT film deposition. This stress balance layer was also found effective to avoid the PZT film cracking even when annealed by rapid thermal annealing with heating-rate up to 10.5 deg. C/s. According to X-ray diffraction analysis and electric properties characterization, crack-free uniform 1-μm-thick PZT film with preferred pervoskite (001) orientation, excellent dielectric constant, as high as 1310, and excellent remanent polarization, as high as 39.8 μC/cm 2 , can be obtained on 4-in. wafer

  14. Smooth muscle adaptation after intestinal transection and resection.

    Science.gov (United States)

    Thompson, J S; Quigley, E M; Adrian, T E

    1996-09-01

    Changes in motor function occur in the intestinal remnant after intestinal resection. Smooth muscle adaptation also occurs, particularly after extensive resection. The time course of these changes and their interrelationship are unclear. Our aim was to evaluate changes in canine smooth muscle structure and function during intestinal adaptation after transection and resection. Twenty-five dogs underwent either transection (N = 10), 50% distal resection (N = 10), or 50% proximal resection (N = 5). Thickness and length of the circular (CM) and longitudinal (LM) muscle layers were measured four and 12 weeks after resection. In vitro length-tension properties and response to a cholinergic agonist were studied in mid-jejunum and mid-ileum. Transection alone caused increased CM length in the jejunum proximal to the transection but did not affect LM length or muscle thickness. A 50% resection resulted in increased length of CM throughout the intestine and thickening of CM and LM near the anastomosis. Active tension of jejunal CM increased transiently four weeks after resection. Active tension in jejunal LM was decreased 12 weeks after transection and resection. Sensitivity of CM to carbachol was similar after transection and resection. It is concluded that: (1) Structural adaptation of both circular and longitudinal muscle occurs after intestinal resection. (2) This process is influenced by the site of the intestinal remnant. (3) Only minor and transient changes occur in smooth muscle function after resection. (4) Factors other than muscle adaptation are likely involved in the changes in motor function seen following massive bowel resection.

  15. Sheet resistivity of silicon wafers implanted with a high current machine

    International Nuclear Information System (INIS)

    Steeples, K.

    1985-01-01

    Silicon wafers, as used in the integrated circuits and semiconductor device industry, have been implanted with all the common dopants using Eaton Corporation's commercially available 'NV' series of high current implanters. Most detailed studies of the implanted wafers have focused on using arsenic and boron as dopants since the transport of these dopants in silicon has been found to be more compatible with the trend towards shrinking device dimensions. Four point probe measurements have been taken on implanted wafers with subsequent annealing to indicate the quality and effect of the implant. The variation of sheet resistance with dose and energy have been studied using a machine in standard condition over the range of 10 14 -10 16 ions/cm 2 and over an energy range of 5-180 keV for arsenic and boron implants into bare wafers and wafers with screen oxides. Dose control at low doses in the Eaton High Current Implanter has been studied over a range of 10 10 -10 13 ions/cm 2 using MOS devices and other measurements. Repeatability of the machines has been obtained by tracking the manufacture of over one hundred machines for nearly three years. With the use of an Eaton Standard Test Implant Procedure for each machine before shipment, it has been shown that the dose repeatability can be as good as 2% (including furnace and four point probe variations) for machine to machine. The repeatability within a single machine was found to be better than 0.5%. Arsenic ion beams have shown excellent independence of end station pressure, as may occur during photoresist outgassing or controlled gas leaks. Boron beams have a higher electron capture cross-section than other commonly used beams and require a dose control compensation for high end station pressure implants to give agreement with the low pressure regime. (orig./TW)

  16. Formation of III–V-on-insulator structures on Si by direct wafer bonding

    International Nuclear Information System (INIS)

    Yokoyama, Masafumi; Iida, Ryo; Ikku, Yuki; Kim, Sanghyeon; Takenaka, Mitsuru; Takagi, Shinichi; Takagi, Hideki; Yasuda, Tetsuji; Yamada, Hisashi; Ichikawa, Osamu; Fukuhara, Noboru; Hata, Masahiko

    2013-01-01

    We have studied the formation of III–V-compound-semiconductors-on-insulator (III–V-OI) structures with thin buried oxide (BOX) layers on Si wafers by using developed direct wafer bonding (DWB). In order to realize III–V-OI MOSFETs with ultrathin body and extremely thin body (ETB) InGaAs-OI channel layers and ultrathin BOX layers, we have developed an electron-cyclotron resonance (ECR) O 2 plasma-assisted DWB process with ECR sputtered SiO 2 BOX layers and a DWB process based on atomic-layer-deposition Al 2 O 3 (ALD-Al 2 O 3 ) BOX layers. It is essential to suppress micro-void generation during wafer bonding process to achieve excellent wafer bonding. We have found that major causes of micro-void generation in DWB processes with ECR-SiO 2 and ALD-Al 2 O 3 BOX layers are desorption of Ar and H 2 O gas, respectively. In order to suppress micro-void generation in the ECR-SiO 2 BOX layers, it is effective to introduce the outgas process before bonding wafers. On the other hand, it is a possible solution for suppressing micro-void generation in the ALD-Al 2 O 3 BOX layers to increase the deposition temperature of the ALD-Al 2 O 3 BOX layers. It is also another possible solution to deposit ALD-Al 2 O 3 BOX layers on thermally oxidized SiO 2 layers, which can absorb the desorption gas from ALD-Al 2 O 3 BOX layers. (invited paper)

  17. Single incision laparoscopic colorectal resection: Our experience

    Directory of Open Access Journals (Sweden)

    Chinnusamy Palanivelu

    2012-01-01

    Full Text Available Background: A prospective case series of single incision multiport laparoscopic colorectal resections for malignancy using conventional laparoscopic trocars and instruments is described. Materials and Methods: Eleven patients (seven men and four women with colonic or rectal pathology underwent single incision multiport laparoscopic colectomy/rectal resection from July till December 2010. Four trocars were placed in a single transumblical incision. The bowel was mobilized laparoscopically and vessels controlled intracorporeally with either intra or extracorporeal anastomosis. Results: Three patients had carcinoma in the caecum, one in the hepatic flexure, two in the rectosigmoid, one in the descending colon, two in the rectum and two had ulcerative pancolitis (one with high grade dysplasia and another with carcinoma rectum. There was no conversion to standard multiport laparoscopy or open surgery. The median age was 52 years (range 24-78 years. The average operating time was 130 min (range 90-210 min. The average incision length was 3.2 cm (2.5-4.0 cm. There were no postoperative complications. The average length of stay was 4.5 days (range 3-8 days. Histopathology showed adequate proximal and distal resection margins with an average lymph node yield of 25 nodes (range 16-30 nodes. Conclusion: Single incision multiport laparoscopic colorectal surgery for malignancy is feasible without extra cost or specialized ports/instrumentation. It does not compromise the oncological radicality of resection. Short-term results are encouraging. Long-term results are awaited.

  18. Hysteroscopic Endometrial Resection in the Management of ...

    African Journals Online (AJOL)

    Background: Abnormal uterine bleeding (AUB) is a major health problem and it is a substantial cause of ill health in women. Medical treatment has a high failure rate and adverse effects. There are few published data on hysteroscopic endometrial resection (HER) in the management of patients with AUB. Objective: To ...

  19. The resection angle in apical surgery

    DEFF Research Database (Denmark)

    von Arx, Thomas; Janner, Simone F M; Jensen, Simon S

    2016-01-01

    OBJECTIVES: The primary objective of the present radiographic study was to analyse the resection angle in apical surgery and its correlation with treatment outcome, type of treated tooth, surgical depth and level of root-end filling. MATERIALS AND METHODS: In the context of a prospective clinical...

  20. COMPARATIVE STUDY OF CONSERVATIVE RESECTION AND ...

    African Journals Online (AJOL)

    1999-05-05

    May 5, 1999 ... an adequate resection of the diseased gland with a wide safety margin followed by excision of cervical lymph nodes when there is any gross evidence of metastatic involvement. This logical basis for either cure or palliation of a ... 50% of cases, they argue that cancer recurrence can be controlled with ...

  1. Resection methodology for PSP data processing: Recent ...

    Indian Academy of Sciences (India)

    ... a simple delta wing in low supersonic flow (M = 1·8). The PSP system utilized for both the cases involve Optrod- B 1 paint, a specially designed UV lamp for excitation and two scientific grade CCD cameras for imaging. Typical results are shown using both the algebraic transformation approach and resection methodology.

  2. Tracheal resection for laryngotracheal stenosis: A retrospective ...

    African Journals Online (AJOL)

    Laryngotracheal stenosis develops when scar tissue forms in the trachea and, rarely, in the larynx itself. Symptoms depend on the degree of airway obstruction and can range from asymptomatic to upper airway obstruction severe enough to cause death. We report on 21 patients who underwent tracheal resection for severe ...

  3. Resection methodology for PSP data processing: Recent ...

    Indian Academy of Sciences (India)

    M. Senthilkumar (Newgen Imaging) 1461 1996 Oct 15 13:05:22

    Abstract. PSP data processing, which primarily involves image alignment and image analysis, is a crucial element in obtaining accurate PSP results. There are two broad approaches to image alignment: the algebraic transformation technique, often called image-warping technique, and resection methodology, which uses ...

  4. What Keeps Postpulmonary Resection Patients in Hospital?

    Directory of Open Access Journals (Sweden)

    T Bardell

    2003-01-01

    Full Text Available BACKGROUND: Prolonged air leak (longer than three days was hypothesized to be the primary cause of extended hospital stays following pulmonary resection. Its effect on length of stay (LOS was compared with that of suboptimal pain control, nausea and vomiting, and other causes. Predictors of prolonged LOS and of prolonged air leaks were investigated.

  5. Ruptured hepatoblastoma treated with primary surgical resection

    African Journals Online (AJOL)

    The aim of this study was to review two cases of ruptured hepatoblastoma treated with primary surgical resection. Hepatoblastoma is the most common primary liver malignancy of childhood, although it remains infrequent. A rare, but serious condition is when the tumor presents with spontaneous rupture. This is a ...

  6. BLADDER NECK RESECTION WITH PRESERVATION OF ...

    African Journals Online (AJOL)

    Conclusion The complication of retrograde ejaculation in young patients who are in need of fertililty may be avoided by preservation of > 1 cm of the supramontanal part during bladder neck resection. La Résection du Col de Vessie avec Préservation de l'Ejaculation Antégrade Objectif Evaluer une nouvelle méthode de ...

  7. Prematurity reduces functional adaptation to intestinal resection in piglets

    DEFF Research Database (Denmark)

    Aunsholt, Lise; Thymann, Thomas; Qvist, Niels

    2015-01-01

    Background: Necrotizing enterocolitis and congenital gastrointestinal malformations in infants often require intestinal resection, with a subsequent risk of short bowel syndrome (SBS). We hypothesized that immediate intestinal adaptation following resection of the distal intestine with placement ...

  8. Surgical resection for hepatocellular carcinoma in Cape Town - A ...

    African Journals Online (AJOL)

    BCC) at our institution between 1990 and 1996, histology of resected specimens, and clinical outcome. Design, Retrospective and prospective study of 14 patients who underwent resection for HCC. Setting. The Hepatobiliary Unit and Liver ...

  9. Extended resection in the treatment of colorectal cancer.

    Science.gov (United States)

    Montesani, C; Ribotta, G; De Milito, R; Pronio, A; D'Amato, A; Narilli, P; Jaus, M

    1991-08-01

    Between 1975 and 1990, 525 patients underwent resection of colorectal cancer in our unit. Of these, 38 had tumour invading adjacent structures and underwent an extended resection. Overall, there were 67 cases treated palliatively. Of these, three were in the group of 38 having an extended resection. When the groups of radical not extended (n = 423) and radical extended resections (n = 35) were compared, respective values for mortality (1.9% vs 0) and morbidity (12.8% vs 11.3%) were not different. Respective local recurrence rates (13% vs 26%) were significantly greater after extended resection. Five-year survival after extended resection was 30%, no different from the general survival rate for standard resections for T2-3 node-positive tumours. Extended resection is thus a safe and important approach for locally advanced tumours.

  10. Good results after repeated resection for colorectal liver metastases

    DEFF Research Database (Denmark)

    Rolff, Hans Christian; Calatayud, Dan; Larsen, Peter Nørgaard

    2012-01-01

    Our study aim was to evaluate the perioperative events, postoperative events and survival after a second liver resection due to colorectal liver metastases (CLM), compared with a matched control group that had only undergone primary liver resection due to CLM....

  11. Augmented reality in bone tumour resection: An experimental study.

    Science.gov (United States)

    Cho, H S; Park, Y K; Gupta, S; Yoon, C; Han, I; Kim, H-S; Choi, H; Hong, J

    2017-03-01

    We evaluated the accuracy of augmented reality (AR)-based navigation assistance through simulation of bone tumours in a pig femur model. We developed an AR-based navigation system for bone tumour resection, which could be used on a tablet PC. To simulate a bone tumour in the pig femur, a cortical window was made in the diaphysis and bone cement was inserted. A total of 133 pig femurs were used and tumour resection was simulated with AR-assisted resection (164 resection in 82 femurs, half by an orthropaedic oncology expert and half by an orthopaedic resident) and resection with the conventional method (82 resection in 41 femurs). In the conventional group, resection was performed after measuring the distance from the edge of the condyle to the expected resection margin with a ruler as per routine clinical practice. The mean error of 164 resections in 82 femurs in the AR group was 1.71 mm (0 to 6). The mean error of 82 resections in 41 femurs in the conventional resection group was 2.64 mm (0 to 11) (p Augmented reality in bone tumour resection: An experimental study. Bone Joint Res 2017;6:137-143. © 2017 Cho et al.

  12. Impact of blood loss on outcome after liver resection

    NARCIS (Netherlands)

    de Boer, M. T.; Molenaar, I. Quintus; Porte, Robert J.

    2007-01-01

    Partial liver resections are the treatment of choice for patients with a malignant liver or bile duct tumor. The most frequent indications for partial liver resections are colorectal metastasis, hepatocellular carcinoma (HCC) and cholangiocarcinoma. Liver resection is the only therapy with a chance

  13. Short-term outcomes following laparoscopic resection for colon cancer.

    LENUS (Irish Health Repository)

    Kavanagh, Dara O

    2011-03-01

    Laparoscopic resection for colon cancer has been proven to have a similar oncological efficacy compared to open resection. Despite this, it is performed by a minority of colorectal surgeons. The aim of our study was to evaluate the short-term clinical, oncological and survival outcomes in all patients undergoing laparoscopic resection for colon cancer.

  14. Iterative learning control for synchronization of reticle stage and wafer stage in step-and-scan lithographic equipment

    Science.gov (United States)

    Li, Lan-lan; Hu, Song; Zhao, Li-xin; Ma, Ping

    2013-08-01

    Lithographic equipments are highly complex machines used to manufacture integrated circuits (ICs). To make larger ICs, a larger lens is required, which, however, is prohibitively expensive. The solution to this problem is to expose a chip not in one flash but in a scanning fashion. For step-and-scan lithographic equipment (wafer scanner), the image quality is decided by many factors, in which synchronization of reticle stage and wafer stage during exposure is a key one. In this paper, the principle of reticle stage and wafer stage was analyzed through investigating the structure of scanners, firstly. While scanning, the reticle stage and wafer stage should scan simultaneously at a high speed and the speed ratio is 1:4. Secondly, an iterative learning controller (ILC) for synchronization of reticle stage and wafer stage is presented. In the controller, a master-slave structure is used, with the wafer stage acting as the master, and the reticle stage as the slave. Since the scanning process of scanner is repetitive, ILC is used to improve tracking performance. A simple design procedure is presented which allows design of the ILC system for the reticle stage and wafer stage independently. Finally, performance of the algorithm is illustrated by simulated on the virtual stages (the reticle stage and wafer stage).The results of simulation experiments and theory analyzing demonstrate that using the proposed controller better synchronization performance can be obtained for the reticle stage and wafer stage in scanner. Theory analysis and experiment shows the method is reasonable and efficient.

  15. SCIL nanoimprint solutions: high-volume soft NIL for wafer scale sub-10nm resolution

    Science.gov (United States)

    Voorkamp, R.; Verschuuren, M. A.; van Brakel, R.

    2016-10-01

    Nano-patterning materials and surfaces can add unique functionalities and properties which cannot be obtained in bulk or micro-structured materials. Examples range from hetro-epitaxy of semiconductor nano-wires to guiding cell expression and growth on medical implants. [1] Due to the cost and throughput requirements conventional nano-patterning techniques such as deep UV lithography (cost and flat substrate demands) and electron-beam lithography (cost, throughput) are not an option. Self-assembly techniques are being considered for IC manufacturing, but require nano-sized guiding patterns, which have to be fabricated in any case.[2] Additionally, the self-assembly process is highly sensitive to the environment and layer thickness, which is difficult to control on non-flat surfaces such as PV silicon wafers or III/V substrates. Laser interference lithography can achieve wafer scale periodic patterns, but is limited by the throughput due to intensity of the laser at the pinhole and only regular patterns are possible where the pattern fill fraction cannot be chosen freely due to the interference condition.[3] Nanoimprint lithography (NIL) is a promising technology for the cost effective fabrication of sub-micron and nano-patterns on large areas. The challenges for NIL are related to the technique being a contact method where a stamp which holds the patterns is required to be brought into intimate contact with the surface of the product. In NIL a strong distinction is made between the type of stamp used, either rigid or soft. Rigid stamps are made from patterned silicon, silica or plastic foils and are capable of sub-10nm resolution and wafer scale patterning. All these materials behave similar at the micro- to nm scale and require high pressures (5 - 50 Bar) to enable conformal contact to be made on wafer scales. Real world conditions such as substrate bow and particle contaminants complicate the use of rigid stamps for wafer scale areas, reducing stamp lifetime and

  16. Non-invasive thermal profiling of silicon wafer surface during RTP using acoustic and signal processing techniques

    Science.gov (United States)

    Syed, Ahmed Rashid

    Among the great physical challenges faced by the current front-end semiconductor equipment manufacturers is the accurate and repeatable surface temperature measurement of wafers during various fabrication steps. Close monitoring of temperature is essential in that it ensures desirable device characteristics to be reliably reproduced across various wafer lots. No where is the need to control temperature more pronounced than it is during Rapid Thermal Processing (RTP) which involves temperature ramp rates in excess of 200°C/s. This dissertation presents an elegant and practical approach to solve the wafer surface temperature estimation problem, in context of RTP, by deploying hardware that acquires the necessary data while preserving the integrity and purity of the wafer. In contrast to the widely used wafer-contacting (and hence contaminating) methods, such as bonded thermocouples, or environment sensitive schemes, such as light-pipes and infrared pyrometry, the proposed research explores the concept of utilizing Lamb (acoustic) waves to detect changes in wafer surface temperature, during RTP. Acoustic waves are transmitted to the wafer via an array of quartz rods that normally props the wafer inside an RTP chamber. These waves are generated using piezoelectric transducers affixed to the bases of the quartz rods. The group velocity of Lamb waves traversing the wafer surface undergoes a monotonic decrease with rise in wafer temperature. The correspondence of delay in phase of the received Lamb waves and the ambient temperature, along all direct paths between sending and receiving transducers, yields a psuedo real-time thermal image of the wafer. Although the custom built hardware-setup implements the above "proof-of-concept" scheme by transceiving acoustic signals at a single frequency, the real-world application will seek to enhance the data acquistion. rate (>1000 temperature measurements per seconds) by sending and receiving Lamb waves at multiple frequencies (by

  17. Clinicoroentgenological assessment of the state of the resected larynx

    Energy Technology Data Exchange (ETDEWEB)

    Demidov, V.P.; Bityutskij, P.G.; Sorokina, N.A.; Kozhanov, L.G. (Akademiya Meditsinskikh Nauk SSSR, Moscow. Inst. Onkologii)

    A study was made of an X-ray picture of the larynx and the state of the pharyngoesophageal anastomosis after salvage operations in 72 patients. Horizontal resection was performed in 42 patients, frontal-lateral in 27 and reconstructive laryngectomy in 3. An analysis of clinicoroentgenological changes showed that their nature depended on the type of resection and the area of resected anatomical structures and elements in the larynx as well as on concomitant manifestations of tumor recurrence or inflammatory disorders. Accurate data on resection type and the area of resectable laryngeal structures are indispensable in assessing X-ray changes.

  18. Benchmarking circumferential resection margin (R1) resection rate for rectal cancer in the neoadjuvant era.

    Science.gov (United States)

    Chambers, W; Collins, G; Warren, B; Cunningham, C; Mortensen, N; Lindsey, I

    2010-09-01

    Circumferential resection margin (CRM) involvement (R1) is used to audit rectal cancer surgical quality. However, when downsizing chemoradiation (dCRT) is used, CRM audits both dCRT and surgery, its use reflecting a high casemix of locally advanced tumours. We aimed to evaluate predictors of R1 and benchmark R1 rates in the dCRT era, and to assess the influence of failure of steps in the multidisciplinary team (MDT) process to CRM involvement. A retrospective analysis of prospectively collected rectal cancer data was undertaken. Patients were classified according to CRM status. Uni- and multivariate analysis was undertaken of risk factors for R1 resection. The contribution of the steps of the MDT process to CRM involvement was assessed. Two hundred and ten rectal cancers were evaluated (68% T3 or T4 on preoperative staging). R1 (microscopic) and R2 (macroscopic) resections occurred in 20 (10%) and 6 patients (3%), respectively. Of several factors associated with R1 resections on univariate analysis, only total mesorectal excision (TME) specimen defects and threatened/involved CRM on preoperative imaging remained as independent predictors of R1 resections on multivariate analysis. Causes of R1 failure by MDT step classification found that less than half were associated with and only 15% solely attributable to a suboptimal TME specimen. Total mesorectal excision specimen defects and staging-predicted threatened or involved CRM are independent strong predictors of R1 resections. In most R1 resections, the TME specimen was intact. It is important to remember the contribution of both the local staging casemix and dCRT failure when using R1 rates to assess purely surgical competence.

  19. Peptide receptor radionuclide therapy as neoadjuvant therapy for resectable or potentially resectable pancreatic neuroendocrine neoplasms.

    Science.gov (United States)

    Partelli, Stefano; Bertani, Emilio; Bartolomei, Mirco; Perali, Carolina; Muffatti, Francesca; Grana, Chiara Maria; Schiavo Lena, Marco; Doglioni, Claudio; Crippa, Stefano; Fazio, Nicola; Zamboni, Giuseppe; Falconi, Massimo

    2018-04-01

    Peptide receptor radionuclide therapy is a valid therapeutic option for pancreatic neuroendocrine neoplasms. The aim of this study was to describe an initial experience with the use of peptide receptor radionuclide therapy as a neoadjuvant agent for resectable or potentially resectable pancreatic neuroendocrine neoplasms. The postoperative outcomes of 23 patients with resectable or potentially resectable pancreatic neuroendocrine neoplasms at high risk of recurrence who underwent neoadjuvant peptide receptor radionuclide therapy (peptide receptor radionuclide therapy group) were compared with 23 patients who underwent upfront surgical operation (upfront surgery group). Patients were matched for tumor size, grade, and stage. Median follow-up was 61 months. The size (median greatest width) of the primary pancreatic neuroendocrine neoplasms decreased after neoadjuvant peptide receptor radionuclide therapy (59 to 50 mm; P=.047). There were no differences in intraoperative and postoperative outcomes and there were no operative deaths, but the risk of developing a pancreatic fistula tended to be less in the peptide receptor radionuclide therapy group when compared to the upfront surgery group (0/23 vs 4/23; P radionuclide therapy group (n= 9/23 vs 17/23; P.2) differed between groups, but progression-free survival in the 31 patients who had an R0 resection seemed to be greater in the 15 patients in the peptide receptor radionuclide therapy group versus 16 patients the upfront group (median progression-free survival not reached vs 36 months; Pradionuclide therapy for resectable or potentially resectable pancreatic neuroendocrine neoplasms in patients with high-risk features of recurrence seems to be beneficial, but well-designed and much larger prospective trials are needed to confirm the safety and the oncologic value of this approach. Copyright © 2017 Elsevier Inc. All rights reserved.

  20. [Pneumonectomy: an alternative to sleeve resection in lung cancer patients?].

    Science.gov (United States)

    Schirren, J; Schirren, M; Passalacqua, M; Bölükbas, S

    2013-06-01

    Lung cancer is localized in the upper lobes in more than half of the cases. The risk of tumor infiltration of centrally located structures, such as bronchi and vessels are enhanced due to the anatomic topography. Pneumonectomy competes with sleeve resection for the surgical resection of centrally located tumors. The present review deals with the question if pneumonectomy should be considered as an alternative to sleeve resection for the treatment of lung cancer. Primary pneumonectomy does not provide any advantage even in advanced nodal disease. Extended lymph node dissection is not a contraindication for sleeve resections. Local recurrence rate is lower after sleeve resections despite the same radicality for both surgical treatment options. Mortality and morbidity rates are significantly lower for sleeve resections. Sleeve resections are associated with prolonged survival and better quality of life even in elderly patients.

  1. Laparoscopic right colon resection with intracorporeal anastomosis.

    Science.gov (United States)

    Chang, Karen; Fakhoury, Mathew; Barnajian, Moshe; Tarta, Cristi; Bergamaschi, Roberto

    2013-05-01

    This study was performed to evaluate short-term clinical outcomes of laparoscopic intracorporeal ileocolic anastomosis following resection of the right colon. This was a retrospective study of selected patients who underwent laparoscopic intracorporeal ileocolic anastomosis following resection of the right colon for tumors or Crohn's disease by a single surgeon from July 2002 through June 2012. Data were retrieved from an Institutional Review Board-approved database. Study end point was postoperative adverse events, including mortality, complications, reoperations, and readmissions at 30 days. Antiperistaltic side-to-side anastomoses were fashioned laparoscopically with a 60-mm-long stapler cartridge and enterocolotomy was hand-sewn intracorporeally in two layers. Values were expressed as medians (ranges) for continuous variables. There were 243 patients (143 females) aged 61 (range = 19-96) years, with body mass index of 29 (18-43) kg/m(2) and ASA 1:2:3:4 of 52:110:77:4; 30 % had previous abdominal surgery and 38 % had a preexisting comorbidity. There were 84 ileocolic resections with ileo ascending anastomosis and 159 right colectomies with ileotransverse anastomosis. Operating time was 135 (60-220) min. Estimated blood loss was 50 (10-600) ml. Specimen extraction site incision length was 4.1 (3-4.4) cm. Conversion rate was 3 % and there was no mortality at 30 days, 15 complications (6.2 %), and 8 reoperations (3.3 %). Readmission rate was 8.7 %. Length of stay was 4 (2-32) days. Pathology confirmed Crohn's disease in 84 patients, adenocarcinoma in 152, and other tumors in 7 patients. Laparoscopic intracorporeal ileocolic anastomosis following resection of the right colon resulted in a favorable outcome in selected patients with Crohn's disease or tumors of the right colon.

  2. Perineal Wound Complications after Abdominoperineal Resection

    OpenAIRE

    Wiatrek, Rebecca L.; Thomas, J. Scott; Papaconstantinou, Harry T.

    2008-01-01

    Perineal wound complications following abdominoperineal resection (APR) is a common occurrence. Risk factors such as operative technique, preoperative radiation therapy, and indication for surgery (i.e., rectal cancer, anal cancer, or inflammatory bowel disease [IBD]) are strong predictors of these complications. Patient risk factors include diabetes, obesity, and smoking. Intraoperative perineal wound management has evolved from open wound packing to primary closure with closed suctioned tra...

  3. Neuropraxia following resection of a retroperitoneal liposarcoma

    Directory of Open Access Journals (Sweden)

    Stevenson Tsiao

    2017-01-01

    Discussion: The patient required only physical therapy and oral prednisone following surgery for treatment of the neuropraxia. She responded well and has regained significant neuromotor function of the affected limb. Cases presenting with post-resection neurological sequelae without any known intraoperative nerve injury may respond very well to conservative treatment. Hence, it is very important to collaborate with Neurology and Physical Therapy to achieve best possible outcome.

  4. Resection of thymoma should include nodal sampling.

    Science.gov (United States)

    Weksler, Benny; Pennathur, Arjun; Sullivan, Jennifer L; Nason, Katie S

    2015-03-01

    Thymoma is best treated by surgical resection; however, no clear guidelines have been created regarding lymph node sampling at the time of resection. Additionally, the prognostic implications of nodal metastases are unclear. The aim of this study was to analyze the prognostic implications of nodal metastases in thymoma. The Surveillance, Epidemiology, and End Results database was queried for patients who underwent surgical resection of thymoma with documented pathologic examination of lymph nodes. The impact of nodal status on survival and thymoma staging was examined. We identified 442 patients who underwent thymoma resection with pathologic evaluation of 1 or more lymph nodes. A median of 2 nodes were sampled per patient. Fifty-nine patients (59 of 442, 13.3%) had ≥ 1 positive node. Patients with positive nodes were younger and had smaller tumors than node-negative patients. Median survival in the node-positive patients was 98 months, compared with 144 months in node-negative patients (P = .013). In multivariable analysis, the presence of positive nodes had a significant, independent, adverse impact on survival (hazard ratio 1.945, 95% confidence interval 1.296-2.919, P = .001). The presence of nodal metastases resulted in a change in classification to a higher stage in 80% of patients, the majority from Masaoka-Koga stage III to stage IV. Nodal status seems to be an important prognostic factor in patients with thymoma. Until the prognostic significance of nodal metastases is better understood, surgical therapy for thymoma should include sampling of regional lymph nodes. Copyright © 2015 The American Association for Thoracic Surgery. Published by Elsevier Inc. All rights reserved.

  5. Thoracic wall reconstruction after tumor resection

    Directory of Open Access Journals (Sweden)

    Kamran eHarati

    2015-10-01

    Full Text Available Introduction: Surgical treatment of malignant thoracic wall tumors represents a formidable challenge. In particular, locally advanced tumors that have already infiltrated critical anatomic structures are associated with a high surgical morbidity and can result in full thickness defects of the thoracic wall. Plastic surgery can reduce this surgical morbidity by reconstructing the thoracic wall through various tissue transfer techniques. Sufficient soft tissue reconstruction of the thoracic wall improves life quality and mitigates functional impairment after extensive resection. The aim of this article is to illustrate the various plastic surgery treatment options in the multimodal therapy of patients with malignant thoracic wall tumors.Material und methods: This article is based on a review of the current literature and the evaluation of a patient database.Results: Several plastic surgical treatment options can be implemented in the curative and palliative therapy of patients with malignant solid tumors of the chest wall. Large soft tissue defects after tumor resection can be covered by local, pedicled or free flaps. In cases of large full-thickness defects, flaps can be combined with polypropylene mesh to improve chest wall stability and to maintain pulmonary function. The success of modern medicine has resulted in an increasing number of patients with prolonged survival suffering from locally advanced tumors that can be painful, malodorous or prone to bleeding. Resection of these tumors followed by thoracic wall reconstruction with viable tissue can substantially enhance the life quality of these patients. Discussion: In curative treatment regimens, chest wall reconstruction enables complete resection of locally advanced tumors and subsequent adjuvant radiotherapy. In palliative disease treatment, stadium plastic surgical techniques of thoracic wall reconstruction provide palliation of tumor-associated morbidity and can therefore improve

  6. Chemical strategies for modifications of the solar cell process, from wafering to emitter diffusion; Chemische Ansaetze zur Neuordnung des Solarzellenprozesses ausgehend vom Wafering bis hin zur Emitterdiffusion

    Energy Technology Data Exchange (ETDEWEB)

    Mayer, Kuno

    2009-11-06

    The paper describes the classic standard industrial solar cell based on monocrystalline silicon and describes new methods of fabrication. The first is an alternative wafering concept using laser microjet cutting instead of multiwire cutting. This method originally uses pure, deionized water; it was modified so that the liquid jet will not only be a liquid light conductor but also a transport medium for etching fluids supporting thermal abrasion of silicon by the laser jet. Two etching fluids were tested experimentally; it was found that water-free fluids based on perfluorinated solvents with very slight additions of gaseous chlorine are superior to all other options. In the second section, the wet chemical process steps between wafering and emitter diffusion (i.e. the first high-temperature step) was to be modified. Alternatives to 2-propanol were to be found in the experimental part. Purification after texturing was to be rationalized in order to reduce the process cost, either by using less chemical substances or by achieving shorter process times. 1-pentanol and p-toluolsulfonic acid were identified as two potential alternatives to 2-propanol as texture additives. Finally, it could be shown that wire-cut substrates processed with the new texturing agents have higher mechanical stabilities than substrates used with the classic texturing agent 2-propanol. [German] Im ersten Kapitel wird die klassische Standard-Industrie-Solarzelle auf der Basis monokristallinen Siliziums vorgestellt. Der bisherige Herstellungsprozess der Standard-Industrie-Solarzelle, der in wesentlichen Teilen darauf abzielt, diese Verluste zu minimieren, dient als Referenz fuer die Entwicklung neuer Fertigungsverfahren, wie sie in dieser Arbeit vorgestellt werden. Den ersten thematischen Schwerpunkt bildet die Entwicklung eines alternativen Wafering-Konzeptes zum Multi-Drahtsaegen. Die Basis des neuen, hier vorgestellten Wafering-Prozesses bildet das Laser-Micro-Jet-Verfahren. Dieses System

  7. Fabrication of capacitive micromachined ultrasonic transducers based on adhesive wafer bonding technique

    International Nuclear Information System (INIS)

    Li, Zhenhao; Wong, Lawrence L P; Chen, Albert I H; Na, Shuai; Yeow, John T W; Sun, Jame

    2016-01-01

    This paper reports the fabrication process of wafer bonded capacitive micromachined ultrasonic transducers (CMUTs) using photosensitive benzocyclobutene as a polymer adhesive. Compared with direct bonding and anodic bonding, polymer adhesive bonding provides good tolerance to wafer surface defects and contamination. In addition, the low process temperature of 250 °C is compatible with standard CMOS processes. Single-element CMUTs consisting of cells with a diameter of 46 µ m and a cavity depth of 323 nm were fabricated. In-air and immersion acoustic characterizations were performed on the fabricated CMUTs, demonstrating their capability for transmitting and receiving ultrasound signals. An in-air resonance frequency of 5.47 MHz was measured by a vibrometer under a bias voltage of 300 V. (paper)

  8. Analyses of crack growth along interface of patterned wafer-level Cu-Cu bonds

    DEFF Research Database (Denmark)

    Tvergaard, Viggo; Hutchinson, John W.

    2009-01-01

    A preliminary theoretical study is carried out of the role of micron-scale patterning on the interface toughness of bonded Cu-to-Cu nanometer-scale films. The work is motivated by the experimental studies of [Tadepalli, R., Turner. K.T., Thompson, C.V., 2008b. Effects of patterning on the interface...... toughness of wafer-level Cu-Cu bonds. Acta Materialia 56, 438-447; Tadepalli, R., Turner, K.T., Thompson, C.V., 2008c. Mixed-mode interface toughness of wafer-level Cu-Cu bonds using asymmetric chevron test. J. Mech. Phys. Solids 56, 707-718.] wherein 400 nm Cu films were deposited in a variety of patterns...... contribution to the macroscopic interface toughness measured by Tadepalli, Turner and Thompson. Highlighted in this study is the difficulty of accurately representing plastic yielding in the thin films and the challenge of capturing the full range of scales in a computational model....

  9. Terahertz wafer-scale mobility mapping of graphene on insulating substrates without a gate

    DEFF Research Database (Denmark)

    Buron, Jonas Due; Mackenzie, David M. A.; Petersen, Dirch Hjorth

    2015-01-01

    spectroscopy. sigma(dc) and tau(SC) are directly extracted from Drude model fits to terahertz conductance spectra obtained in each pixel of 10 x 10 cm(2) maps with a 400 mu m step size. sigma(dc)- and tau(SC)-maps are translated into mu(drift) and N-S maps through Boltzmann transport theory for graphene charge......We demonstrate wafer-scale, non-contact mapping of essential carrier transport parameters, carrier mobility (mu(drift)), carrier density (N-S), DC sheet conductance (sigma(dc)), and carrier scattering time (tau(SC)) in CVD graphene, using spatially resolved terahertz time-domain conductance...... carriers and these parameters are directly compared to van der Pauw device measurements on the same wafer. The technique is compatible with all substrate materials that exhibit a reasonably low absorption coefficient for terahertz radiation. This includes many materials used for transferring CVD graphene...

  10. Silicon Wafer Fabrication and Microchannel for Cooling System in ALICE ITS

    CERN Document Server

    Pasuwan, Patrawan

    2013-01-01

    My summer student project covered details of the upgrade of Inner Tracking System (ITS) of the ALICE detector. The tasks are divided in two parts. First was on silicon wafer dicing technology and its resistivity under the supervision of Petra Riedler. Next was on silicon wafer microfabrication and cooling system in microchannel under the supervision of Andrea Francescon. ITS upgrade was proposed for better detection performance and reduction of budget. Detectors in the ITS are composed of monolithic silicon pixel chips. The thickness of the chips was proposed to be 50 μm so that particles that pass through them do not lose too much momentum. Working with very thin chips requires suitable dicing technology. Sum- mary of dicing technology is proposed for the most suitable dicing technique. Properties of the chip can be denoted by observing its resistivity. Literature reviews on surface resistivity profile measurement is represented for consideration. Cooling system is very important for the detector. Fluid t...

  11. On the design of GaN vertical MESFETs on commercial LED sapphire wafers

    Science.gov (United States)

    Atalla, Mahmoud R. M.; Noor Elahi, Asim M.; Mo, Chen; Jiang, Zhenyu; Liu, Jie; Ashok, S.; Xu, Jian

    2016-12-01

    Design of GaN-based vertical metal-semiconductor field-effect transistors (MESFETs) on commercial light-emitting-diode (LED) epi-wafers has been proposed and proof of principle devices have been fabricated. In order to better understand the IV curves, these devices have been simulated using the charge transport model. It was found that shrinking the drain pillar size would significantly help in reaching cut-off at much lower gate bias even at high carrier concentration of unintentionally doped GaN and considerable leakage current caused by the Schottky barrier lowering. The realization of these vertical MESFETs on LED wafers would allow their chip-level integration. This would open a way to many intelligent lighting applications like on-chip current regulator and signal regulation/communication in display technology.

  12. Stealth dicing of sapphire wafers with near infra-red femtosecond pulses

    Science.gov (United States)

    Yadav, Amit; Kbashi, Hani; Kolpakov, Stanislav; Gordon, Neil; Zhou, Kaiming; Rafailov, Edik U.

    2017-05-01

    The quality of the reflecting faces after dicing is critical for the fabrication of efficient and stable laser diodes emitting in the green-violet region. However, high-quality faces can be difficult to achieve for devices grown on a sapphire substrate as this material is difficult to cleave cleanly. We have therefore investigated a technology known as "stealth dicing". The technology uses a pulsed laser to damage a plane of material inside of the wafer due to multi-photon absorption instead of cutting through the wafer surface. If the damage is induced in a line of stress points, the sample can then be cleaved easily along the damaged plane to leave a high-quality surface. The use of this technique also reduces thermal damage and debris.

  13. Wafer-Level Patterned and Aligned Polymer Nanowire/Micro- and Nanotube Arrays on any Substrate

    KAUST Repository

    Morber, Jenny Ruth

    2009-05-25

    A study was conducted to fabricate wafer-level patterned and aligned polymer nanowire (PNW), micro- and nanotube arrays (PNT), which were created by exposing the polymer material to plasma etching. The approach for producing wafer-level aligned PNWs involved a one-step inductively coupled plasma (ICP) reactive ion etching process. The polymer nanowire array was fabricated in an ICP reactive ion milling chamber with a pressure of 10mTorr. Argon (Ar), O 2, and CF4 gases were released into the chamber as etchants at flow rates of 15 sccm, 10 sccm, and 40 sccm. Inert gasses, such as Ar-form positive ions were incorporated to serve as a physical component to assist in the material degradation process. One power source (400 W) was used to generate dense plasma from the input gases, while another power source applied a voltage of approximately 600V to accelerate the plasma toward the substrate.

  14. A new method for wafer quality monitoring using semiconductor process big data

    Science.gov (United States)

    Sohn, Younghoon; Lee, Hyun; Yang, Yusin; Jun, Chungsam

    2017-03-01

    In this paper we proposed a new semiconductor quality monitoring methodology - Process Sensor Log Analysis (PSLA) - using process sensor data for the detection of wafer defectivity and quality monitoring. We developed exclusive key parameter selection algorithm and user friendly system which is able to handle large amount of big data very effectively. Several production wafers were selected and analyzed based on the risk analysis of process driven defects, for example alignment quality of process layers. Thickness of spin-coated material can be measured using PSLA without conventional metrology process. In addition, chip yield impact was verified by matching key parameter changes with electrical die sort (EDS) fail maps at the end of the production step. From this work, we were able to determine that process robustness and product yields could be improved by monitoring the key factors in the process big data.

  15. ILT based defect simulation of inspection images accurately predicts mask defect printability on wafer

    Science.gov (United States)

    Deep, Prakash; Paninjath, Sankaranarayanan; Pereira, Mark; Buck, Peter

    2016-05-01

    At advanced technology nodes mask complexity has been increased because of large-scale use of resolution enhancement technologies (RET) which includes Optical Proximity Correction (OPC), Inverse Lithography Technology (ILT) and Source Mask Optimization (SMO). The number of defects detected during inspection of such mask increased drastically and differentiation of critical and non-critical defects are more challenging, complex and time consuming. Because of significant defectivity of EUVL masks and non-availability of actinic inspection, it is important and also challenging to predict the criticality of defects for printability on wafer. This is one of the significant barriers for the adoption of EUVL for semiconductor manufacturing. Techniques to decide criticality of defects from images captured using non actinic inspection images is desired till actinic inspection is not available. High resolution inspection of photomask images detects many defects which are used for process and mask qualification. Repairing all defects is not practical and probably not required, however it's imperative to know which defects are severe enough to impact wafer before repair. Additionally, wafer printability check is always desired after repairing a defect. AIMSTM review is the industry standard for this, however doing AIMSTM review for all defects is expensive and very time consuming. Fast, accurate and an economical mechanism is desired which can predict defect printability on wafer accurately and quickly from images captured using high resolution inspection machine. Predicting defect printability from such images is challenging due to the fact that the high resolution images do not correlate with actual mask contours. The challenge is increased due to use of different optical condition during inspection other than actual scanner condition, and defects found in such images do not have correlation with actual impact on wafer. Our automated defect simulation tool predicts

  16. [Resection of intracardiac myxoma. Case report].

    Science.gov (United States)

    Carmona-Delgado, Víctor Manuel; Deloya-Maldonado, Angélica María; Carranza-Bernal, María Lourdes; Hinojosa-Pérez, Arturo; Farías-Mayene, Leobardo

    2017-01-01

    Myxomas are the most common benign cardiac tumors, which are considered emergency surgery. The resection should not be delayed because 8-9% of affected patients may die due to intracardiac blood flow obstruction. We presente a clinical case of a 47 year old female, history of dyslipidemia. Disease starts with retrosternal oppression feeling, dyspnea on moderate exercise, dizziness, pain in joints hands. Arrhytmic heart sounds, diastolic mitral murmur II/IV, breth sounds present, no lymph. Laboratory: hemoglobin 11.0, leucocyte 9000, glucose 96 mg/dL, chest RX medium arch prominence cardiac silhouette. ECO transthoracic LVEF 60 %, with left atrial intracardiac tumor 13x11 cm, pedicle fixed the interatrial septum, the mitral valve bulges, with mild mitral valve. Half sternotomy is performed intracardiac tumor resection, pericardial placement interatrial with extracorporeal circulation support 65', aortic clamping time of 40'. Intracardiac tumor surgical findings interatrial septum fixed to left side, pedicle, rounded, yellow, multiloculated, soft, 13x10 cm in diameter. Histopathological diagnosis cardiac myxoma. We conclude that the tumor resection was carried in a timely manner with satisfactory evolution.

  17. Incidental Transient Cortical Blindness after Lung Resection

    Science.gov (United States)

    Oncel, Murat; Sunam, Guven Sadi; Varoglu, Asuman Orhan; Karabagli, Hakan; Yildiran, Huseyin

    2016-01-01

    Transient vision loss after major surgical procedures is a rare clinical complication. The most common etiologies are cardiac, spinal, head, and neck surgeries. There has been no report on vision loss after lung resection. A 65-year-old man was admitted to our clinic with lung cancer. Resection was performed using right upper lobectomy with no complications. Cortical blindness developed 12 hours later in the postoperative period. Results from magnetic resonance imaging and diffusion-weighted investigations were normal. The neurologic examination was normal. The blood glucose level was 92 mg/dL and blood gas analysis showed a PO 2 of 82 mm Hg. After 24 hours, the patient began to see and could count fingers, and his vision was fully restored within 72 hours after this point. Autonomic dysfunction due to impaired microvascular structures in diabetes mellitus may induce posterior circulation dysfunction, even when the hemodynamic state is normal in the perioperative period. The physician must keep in mind that vision loss may occur after lung resection due to autonomic dysfunction, especially in older patients with diabetes mellitus. PMID:28824977

  18. Increasing reticle inspection efficiency and reducing wafer print-checks using automated defect classification and simulation

    Science.gov (United States)

    Ryu, Sung Jae; Lim, Sung Taek; Vacca, Anthony; Fiekowsky, Peter; Fiekowsky, Dan

    2013-09-01

    IC fabs inspect critical masks on a regular basis to ensure high wafer yields. These requalification inspections are costly for many reasons including the capital equipment, system maintenance, and labor costs. In addition, masks typically remain in the "requal" phase for extended, non-productive periods of time. The overall "requal" cycle time in which reticles remain non-productive is challenging to control. Shipping schedules can slip when wafer lots are put on hold until the master critical layer reticle is returned to production. Unfortunately, substituting backup critical layer reticles can significantly reduce an otherwise tightly controlled process window adversely affecting wafer yields. One major requal cycle time component is the disposition process of mask inspections containing hundreds of defects. Not only is precious non-productive time extended by reviewing hundreds of potentially yield-limiting detections, each additional classification increases the risk of manual review techniques accidentally passing real yield limiting defects. Even assuming all defects of interest are flagged by operators, how can any person's judgment be confident regarding lithographic impact of such defects? The time reticles spend away from scanners combined with potential yield loss due to lithographic uncertainty presents significant cycle time loss and increased production costs. Fortunately, a software program has been developed which automates defect classification with simulated printability measurement greatly reducing requal cycle time and improving overall disposition accuracy. This product, called ADAS (Auto Defect Analysis System), has been tested in both engineering and high-volume production environments with very successful results. In this paper, data is presented supporting significant reduction for costly wafer print checks, improved inspection area productivity, and minimized risk of misclassified yield limiting defects.

  19. Real-time direct and diffraction X-ray imaging of irregular silicon wafer breakage

    Directory of Open Access Journals (Sweden)

    Alexander Rack

    2016-03-01

    Full Text Available Fracture and breakage of single crystals, particularly of silicon wafers, are multi-scale problems: the crack tip starts propagating on an atomic scale with the breaking of chemical bonds, forms crack fronts through the crystal on the micrometre scale and ends macroscopically in catastrophic wafer shattering. Total wafer breakage is a severe problem for the semiconductor industry, not only during handling but also during temperature treatments, leading to million-dollar costs per annum in a device production line. Knowledge of the relevant dynamics governing perfect cleavage along the {111} or {110} faces, and of the deflection into higher indexed {hkl} faces of higher energy, is scarce due to the high velocity of the process. Imaging techniques are commonly limited to depicting only the state of a wafer before the crack and in the final state. This paper presents, for the first time, in situ high-speed crack propagation under thermal stress, imaged simultaneously in direct transmission and diffraction X-ray imaging. It shows how the propagating crack tip and the related strain field can be tracked in the phase-contrast and diffracted images, respectively. Movies with a time resolution of microseconds per frame reveal that the strain and crack tip do not propagate continuously or at a constant speed. Jumps in the crack tip position indicate pinning of the crack tip for about 1–2 ms followed by jumps faster than 2–6 m s−1, leading to a macroscopically observed average velocity of 0.028–0.055 m s−1. The presented results also give a proof of concept that the described X-ray technique is compatible with studying ultra-fast cracks up to the speed of sound.

  20. Fabrication of a mechanically aligned single-wafer MEMS turbine with turbocharger

    Science.gov (United States)

    Pelekies, S. O.; Schuhmann, T.; Gardner, W. G.; Camacho, A.; Protz, J. M.

    2010-10-01

    We describe the fabrication of a turbocharged, microelectromechanical system (MEMS) turbine. The turbine will be part of a standalone power unit and includes extra layers to connect the turbine to a generator. The project goal is to demonstrate the successful combination of several features, namely: silicon fusion bonding (SFB), a micro turbocharger [2], two rotors, mechanical alignment between two wafers [1], and the use of only one 5" silicon wafer. The dimension of the actual turbine casing will be 14mm. The turbine rotor will have a diameter of 8mm. Given these dimensions, MEMS processes are an adequate way to fabricate the device, but it will be necessary to stack up seven different layers to build the turbine, as it is not possible to construct it out of one thick wafer. SFB will be used for bonding because it permits the great precision necessary for high quality alignment. Yet a more precise alignment will be necessary between the layers that contain the turbine rotor, to decrease imbalance and guarantee operation at a very high rpm. To achieve these tight tolerances, a mechanical alignment feature announced by Liudi Jiang [1] is used. The alignment accuracy is expected to be around 200nm. Despite the fact that the turbine consists of multiple layers, it will be fabricated on only one silicon-on-insulator (SOI) wafer. As a result, all layers are exposed to the same process flow. The fabrication process includes MEMS technology as photolithography, nine deep reactive ion etching (DRIE) steps, and six SFB operations. A total of 14 masks are necessary for the fabrication.

  1. Photolithography diagnostic expert systems: a systematic approach to problem solving in a wafer fabrication facility

    Science.gov (United States)

    Weatherwax Scott, Caroline; Tsareff, Christopher R.

    1990-06-01

    One of the main goals of process engineering in the semiconductor industry is to improve wafer fabrication productivity and throughput. Engineers must work continuously toward this goal in addition to performing sustaining and development tasks. To accomplish these objectives, managers must make efficient use of engineering resources. One of the tools being used to improve efficiency is the diagnostic expert system. Expert systems are knowledge based computer programs designed to lead the user through the analysis and solution of a problem. Several photolithography diagnostic expert systems have been implemented at the Hughes Technology Center to provide a systematic approach to process problem solving. This systematic approach was achieved by documenting cause and effect analyses for a wide variety of processing problems. This knowledge was organized in the form of IF-THEN rules, a common structure for knowledge representation in expert system technology. These rules form the knowledge base of the expert system which is stored in the computer. The systems also include the problem solving methodology used by the expert when addressing a problem in his area of expertise. Operators now use the expert systems to solve many process problems without engineering assistance. The systems also facilitate the collection of appropriate data to assist engineering in solving unanticipated problems. Currently, several expert systems have been implemented to cover all aspects of the photolithography process. The systems, which have been in use for over a year, include wafer surface preparation (HMDS), photoresist coat and softbake, align and expose on a wafer stepper, and develop inspection. These systems are part of a plan to implement an expert system diagnostic environment throughout the wafer fabrication facility. In this paper, the systems' construction is described, including knowledge acquisition, rule construction, knowledge refinement, testing, and evaluation. The roles

  2. [Duodenum-preserving total pancreatic head resection and pancreatic head resection with segmental duodenostomy].

    Science.gov (United States)

    Takada, Tadahiro; Yasuda, Hideki; Nagashima, Ikuo; Amano, Hodaka; Yoshiada, Masahiro; Toyota, Naoyuki

    2003-06-01

    A duodenum-preserving pancreatic head resection (DPPHR) was first reported by Beger et al. in 1980. However, its application has been limited to chronic pancreatitis because of it is a subtotal pancreatic head resection. In 1990, we reported duodenum-preserving total pancreatic head resection (DPTPHR) in 26 cases. This opened the way for total pancreatic head resection, expanding the application of this approach to tumorigenic morbidities such as intraductal papillary mucinous tumor (IMPT), other benign tumors, and small pancreatic cancers. On the other hand, Nakao et al. reported pancreatic head resection with segmental duodenectomy (PHRSD) as an alternative pylorus-preserving pancreatoduodenectomy technique in 24 cases. Hirata et al. also reported this technique as a new pylorus-preserving pancreatoduodenostomy with increased vessel preservation. When performing DPTPHR, the surgeon should ensure adequate duodenal blood supply. Avoidance of duodenal ischemia is very important in this operation, and thus it is necessary to maintain blood flow in the posterior pancreatoduodenal artery and to preserve the mesoduodenal vessels. Postoperative pancreatic functional tests reveal that DPTPHR is superior to PPPD, including PHSRD, because the entire duodenum and duodenal integrity is very important for postoperative pancreatic function.

  3. Colonoscopic resection of lateral spreading tumours: a prospective analysis of endoscopic mucosal resection.

    Science.gov (United States)

    Hurlstone, D P; Sanders, D S; Cross, S S; Adam, I; Shorthouse, A J; Brown, S; Drew, K; Lobo, A J

    2004-09-01

    Lateral spreading tumours are superficial spreading neoplasms now increasingly diagnosed using chromoscopic colonoscopy. The clinicopathological features and safety of endoscopic mucosal resection for lateral spreading tumours (G-type "aggregate" and F-type "flat") has yet to be clarified in Western cohorts. Eighty two patients underwent magnification chromoscopic colonoscopy using the Olympus CF240Z by a single endoscopist. All patients had received a previous colonoscopy where an endoscopic diagnosis of lateral spreading tumour was made. All lesions were examined initially using indigo carmine chromoscopy to delineate contour followed by crystal violet for magnification crypt pattern analysis. A 20 MHz "mini probe" ultrasound was used if T2 disease was suspected. Following endoscopic mucosal resection, patients were followed up at 3, 6, 12, and 24 months using total colonoscopy. Eighty two lateral spreading tumours were diagnosed in 80 patients (32% (26/82) F-type and 68% (56/82) G-type). G-type lesions were larger than F-type (G-type mean 42 (SD 14) mm v F-type 24 (6.4) mm; plateral spreading tumours using endoscopic mucosal resection at two years of follow-up was 96% (56/58). Endoscopic mucosal resection for lateral spreading tumours, staged as T1, is a safe and effective treatment despite their large size. Endoscopic mucosal resection may be an alternative to surgery in selected patients.

  4. Sample pretreatment for the determination of metal impurities in silicon wafer

    International Nuclear Information System (INIS)

    Chung, H. Y.; Kim, Y. H.; Yoo, H. D.; Lee, S. H.

    1999-01-01

    The analytical results obtained by microwave digestion and acid digestion methods for sample pretreatment to determine metal impurities in silicon wafer by inductively coupled plasma--mass spectrometry(ICP-MS) were compared. In order to decompose the silicon wafer, a mixed solution of HNO 3 and HF was added to the sample and the metal elements were determined after removing the silicon matrix by evaporating silicon in the form of Si-F. The recovery percentages of Ni, Cr and Fe were found to be 95∼106% for both microwave digestion and acid digestion methods. The recovery percentage of Cu obtained by the acid digestion method was higher than that obtained by the microwave digestion method. For Zn, however, the microwave digestion method gave better result than the acid digestion method. Fe was added to a silicon wafer using a spin coater. The concentration of Fe in this sample was determined by ICP-MS, and the same results were obtained in the two pretreatment methods

  5. Electron multibeam technology for mask and wafer writing at 0.1 nm address grid

    Science.gov (United States)

    Platzgummer, Elmar; Klein, Christof; Loeschner, Hans

    2013-07-01

    IMS Nanofabrication realized a 50 keV electron multibeam proof-of-concept (POC) tool confirming writing principles with 0.1 nm address grid and lithography performance capability. The POC system achieves the predicted 5 nm 1 sigma blur across the 82 μm×82 μm array of 512×512 (262,144) programmable 20 nm beams. 24-nm half pitch (HP) has been demonstrated and complex patterns have been written in scanning stripe exposure mode. The first production worthy system for the 11-nm HP mask node is scheduled for 2014 (Alpha), 2015 (Beta), and first-generation high-volume manufacturing multibeam mask writer (MBMW) tools in 2016. In these MBMW systems the max beam current through the column is 1 μA. The new architecture has also the potential for 1× mask (master template) writing. Substantial further developments are needed for maskless e-beam direct write (EBDW) applications as a beam current of >2 mA is needed to achieve 100 wafer per hour industrial targets for 300 mm wafer size. Necessary productivity enhancements of more than three orders of magnitude are only possible by shrinking the multibeam optics such that 50 to 100 subcolumns can be placed on the area of a 300 mm wafer and by clustering 10 to 20 multicolumn tools. An overview of current EBDW efforts is provided.

  6. Silicon crystals: Process for manufacturing wafer-like silicon crystals with a columnar structure

    Science.gov (United States)

    Authier, B.

    1978-01-01

    Wafer-like crystals suitable for making solar cells are formed by pouring molten Si containing suitable dopants into a mold of the desired shape and allowing it to solidify in a temperature gradient, whereby the large surface of the melt in contact with the mold is kept at less than 200 D and the free surface is kept at a temperature of 200-1000 D higher, but below the melting point of Si. The mold can also be made in the form of a slit, whereby the 2 sides of the mold are kept at different temperatures. A mold was milled in the surface of a cylindrical graphite block 200 mm in diameter. The granite block was induction heated and the bottom of the mold was cooled by means of a water-cooled Cu plate, so that the surface of the mold in contact with one of the largest surfaces of the melt was held at approximately 800 D. The free surface of the melt was subjected to thermal radiation from a graphite plate located 2 mm from the surface and heated to 1500 D. The Si crystal formed after slow cooling to room temperature had a columnar structure and was cut with a diamond saw into wafers approximately 500 mm thick. Solar cells prepared from these wafers had efficiencies of 10 to 11%.

  7. Culture of neural cells on silicon wafers with nano-scale surface topograph.

    Science.gov (United States)

    Fan, Y W; Cui, F Z; Hou, S P; Xu, Q Y; Chen, L N; Lee, I-S

    2002-10-15

    The adherence and viability of central neural cells (substantia nigra) on a thin layer of SiO(2) on Si wafers with different surface roughness were investigated. Variable roughness of the Si wafer surface was achieved by etching. The nano-scale surface topography was evaluated by atomic force microscopy. The adherence and subsequent viability of the cells on the wafer were examined by scanning electron microscopy (SEM) and fluorescence immunostaining of tyrosine hydroxylase (TH). It is found that the surface roughness significantly affected cell adhesion and viability. Cells survived for over 5 days with normal morphology and expressed neuronal TH when grown on surfaces with an average roughness (Ra) ranging from 20 to 50 nm. However, cell adherence was adversely affected when surfaces with Ra less than 10 nm and rough surfaces with Ra above 70 nm were used as the substrate. Such a simple preparation procedure may provide a suitable interface surface for silicon-based devices and neurones or other living tissues.

  8. Wafer-level micro-optics: trends in manufacturing, testing, packaging, and applications

    Science.gov (United States)

    Voelkel, Reinhard; Gong, Li; Rieck, Juergen; Zheng, Alan

    2012-11-01

    Micro-optics is an indispensable key enabling technology (KET) for many products and applications today. Probably the most prestigious examples are the diffractive light shaping elements used in high-end DUV lithography steppers. Highly efficient refractive and diffractive micro-optical elements are used for precise beam and pupil shaping. Micro-optics had a major impact on the reduction of aberrations and diffraction effects in projection lithography, allowing a resolution enhancement from 250 nm to 45 nm within the last decade. Micro-optics also plays a decisive role in medical devices (endoscopes, ophthalmology), in all laser-based devices and fiber communication networks (supercomputer, ROADM), bringing high-speed internet to our homes (FTTH). Even our modern smart phones contain a variety of micro-optical elements. For example, LED flashlight shaping elements, the secondary camera, and ambient light and proximity sensors. Wherever light is involved, micro-optics offers the chance to further miniaturize a device, to improve its performance, or to reduce manufacturing and packaging costs. Wafer-scale micro-optics fabrication is based on technology established by semiconductor industry. Thousands of components are fabricated in parallel on a wafer. We report on the state of the art in wafer-based manufacturing, testing, packaging and present examples and applications for micro-optical components and systems.

  9. Interactions of double patterning technology with wafer processing, OPC and design flows

    Science.gov (United States)

    Lucas, Kevin; Cork, Chris; Miloslavsky, Alex; Luk-Pat, Gerry; Barnes, Levi; Hapli, John; Lewellen, John; Rollins, Greg; Wiaux, Vincent; Verhaegen, Staf

    2008-03-01

    Double patterning technology (DPT) is one of the main options for printing logic devices with half-pitch less than 45nm; and flash and DRAM memory devices with half-pitch less than 40nm. DPT methods decompose the original design intent into two individual masking layers which are each patterned using single exposures and existing 193nm lithography tools. The results of the individual patterning layers combine to re-create the design intent pattern on the wafer. In this paper we study interactions of DPT with lithography, masks synthesis and physical design flows. Double exposure and etch patterning steps create complexity for both process and design flows. DPT decomposition is a critical software step which will be performed in physical design and also in mask synthesis. Decomposition includes cutting (splitting) of original design intent polygons into multiple polygons where required; and coloring of the resulting polygons. We evaluate the ability to meet key physical design goals such as: reduce circuit area; minimize rework; ensure DPT compliance; guarantee patterning robustness on individual layer targets; ensure symmetric wafer results; and create uniform wafer density for the individual patterning layers.

  10. Analysis of Processing Mechanism in Stealth Dicing of Ultra Thin Silicon Wafer

    Science.gov (United States)

    Ohmura, Etsuji; Kumagai, Masayoshi; Nakano, Makoto; Kuno, Koji; Fukumitsu, Kenshi; Morita, Hideki

    In this study, “stealth dicing” (SD) was applied to ultra thin wafers 50 μm in thickness. A coupling problem composed of focused laser propagation in single crystal silicon, along with laser absorption, temperature rise and heat conduction was analyzed by considering the temperature dependence of the absorption coefficient. When the depth of the focal plane is too shallow, the laser is also absorbed at the surface as the thermal shock wave reaches the surface. As a result, not only is an internal modified layer generated but ablation occurs at the surface as well. When the laser is focused at the surface, strong ablation occurs. Ablation at the surface is unfavorable because of the debris pollution and thermal effect on the device domain. It was concluded that there is a suitable depth for the focal plane so that the thermal shock wave propagates inside the wafer only. The optimum irradiating conditions such as pulse energy, pulse width, spot radius, and depth of focal plane can be estimated theoretically also for ultra thin wafer.

  11. Crack Detection in Single-Crystalline Silicon Wafer Using Laser Generated Lamb Wave

    Directory of Open Access Journals (Sweden)

    Min-Kyoo Song

    2013-01-01

    Full Text Available In the semiconductor industry, with increasing requirements for high performance, high capacity, high reliability, and compact components, the crack has been one of the most critical issues in accordance with the growing requirement of the wafer-thinning in recent years. Previous researchers presented the crack detection on the silicon wafers with the air-coupled ultrasonic method successfully. However, the high impedance mismatching will be the problem in the industrial field. In this paper, in order to detect the crack, we propose a laser generated Lamb wave method which is not only noncontact, but also reliable for the measurement. The laser-ultrasonic generator and the laser-interferometer are used as a transmitter and a receiver, respectively. We firstly verified the identification of S0 and A0 lamb wave modes and then conducted the crack detection under the thermoelastic regime. The experimental results showed that S0 and A0 modes of lamb wave were clearly generated and detected, and in the case of the crack detection, the estimated crack size by 6 dB drop method was almost equal to the actual crack size. So, the proposed method is expected to make it possible to detect the crack in the silicon wafer in the industrial fields.

  12. In situ beam angle measurement in a multi-wafer high current ion implanter

    International Nuclear Information System (INIS)

    Freer, B.S.; Reece, R.N.; Graf, M.A.; Parrill, T.; Polner, D.

    2005-01-01

    Direct, in situ measurement of the average angle and angular content of an ion beam in a multi-wafer ion implanter is reported for the first time. A new type of structure and method are described. The structures are located on the spinning disk, allowing precise angular alignment to the wafers. Current that passes through the structures is known to be within a range of angles and is detected behind the disk. By varying the angle of the disk around two axes, beam current versus angle is mapped and the average angle and angular spread are calculated. The average angle measured in this way is found to be consistent with that obtained by other techniques, including beam centroid offset and wafer channeling methods. Average angle of low energy beams, for which it is difficult to use other direct methods, is explored. A 'pencil beam' system is shown to give average angle repeatability of 0.13 deg. (1σ) or less, for two low energy beams under normal tuning variations, even though no effort was made to control the angle

  13. Room-temperature direct bonding of silicon and quartz glass wafers

    Science.gov (United States)

    Wang, Chenxi; Wang, Yuan; Tian, Yanhong; Wang, Chunqing; Suga, Tadatomo

    2017-05-01

    We demonstrate a facile bonding method for combining Si/Si, Si/quartz, and quartz/quartz wafers at room temperature (˜25 °C) using a one-step O2/CF4/H2O plasma treatment. The bonding strengths were significantly improved by adding a small amount of CF4 into the oxygen plasma, such that reliable and tight bonding was obtained after storage in ambient air for 24 h, even without employing heat. Moreover, by introducing water vapor during O2/CF4 plasma treatment, uniform wafer bonding was spontaneously achieved without applying an external force. The fluorinated surface asperities appear to be softened more easily by the interfacial water stress corrosion, enabling reliable bonding at room temperature. Additionally, adding an optimized amount of water vapor to the O2/CF4 plasma increases sufficiently the amount of hydroxyl groups without eliminating the CF4 effect. The additional water adsorbed on the surface may help to close the gap between the bonded wafers, resulting in better bonding efficiency.

  14. Chip yield for FETs fabricated on low-surface-defect GaAs wafers grown by a new MBE system

    Energy Technology Data Exchange (ETDEWEB)

    Kato, S.; Shigeta, J.; Miyata, T.; Kawata, M. (Central Research Laboratory, Hitachi Ltd., Tokyo (Japan)); Tamura, N. (Kasado Works, Hitachi Ltd., Yamachuci (Japan)); Takahashi, K. (Mechanical Research Laboratory, Hitachi Ltd., Ibaraki (Japan))

    1993-06-15

    A very low defect density is achieved with a new MBE system, in which the diameter of the top-heated Ga cell is as big as 60 mm and the distance between the wafer and the cell is optimized at 450 mm by simulation. This system grows GaAs wafers with a defect density of 14.6 cm[sup -2] for defects larger than 0.67 [mu]m[sup 2]. Our chip yield estimation for field effect transistors in the LSIs fabricated on the wafers shows that the grown wafer can integrate 100,000 FETs if each FET gate is 0.3 [mu]m long and 5 [mu]m wide and a chip yield of 42% is assumed

  15. New plant designs for aqueous etching and electroforming of wafers; Neues modulares Anlagenkonzept fuer nasschemische Aetzprozesse und die Wafergalvanoformung

    Energy Technology Data Exchange (ETDEWEB)

    Guttmann, Markus; Kaiser, Konradin; Muth, Stephanie [Karlsruher Institut fuer Technologie, Karlsruhe (Germany). Inst. fuer Mikrostrukturtechnik; Moritz, Hans [silicet AG, Lohfelden (Germany); Schmidt, Ralf; Zwanzig, Michael [Fraunhofer-Institut fuer Zuverlaessigkeit und Mikrointegration (IZM), Berlin (Germany); Hofmann, Lutz [TU Chemnitz (Germany). Zentrum fuer Mikrotechnologien; Schubert, Ina [Fraunhofer-Einrichtung fuer Elektronische Nanosysteme (ENAS), Chemnitz (Germany)

    2009-07-01

    In order to carry out a study of wafer patterning, equipment was developed for safe handling of silicon wafers from 2 to 8 inch diameters. The unit can be safely and relatively straightforwardly operated by personnel, using a wide range of etchants and electrochemical deposition processes. The design also allows the effects of electrolyte flowrate in the process chamber confronting the silicon wafer, to be assessed. These features were utilised to study copper and nickel electrodeposition to pattern the wafer surface. (orig.) [German] Zur Untersuchung der Strukturierung von Wafern wurde eine Prozesseinheit zur bruchsicheren Aufnahme von Siliziumwafern mit Durchmessern zwischen zwei und acht Zoll entwickelt. Die Einheit kann relativ einfach und mit hoher Sicherheit fuer die handhabenden Personen mit den unterschiedlichsten Medien zum Aetzen oder galvanotechnischen Aufbau betrieben werden. Die Anordnung ermoeglicht zudem die gezielte Beeinflussung der Stroemung im Prozessraum vor der Waferoberflaeche. Die Moeglichkeiten zur Untersuchung werden an der Nickel- und Kupferabscheidung zur Herstellung von Strukturen aufgezeigt. (orig.)

  16. Surgical resection of synchronously metastatic adrenocortical cancer.

    Science.gov (United States)

    Dy, Benzon M; Strajina, Veljko; Cayo, Ashley K; Richards, Melanie L; Farley, David R; Grant, Clive S; Harmsen, William S; Evans, Doug B; Grubbs, Elizabeth G; Bible, Keith C; Young, William F; Perrier, Nancy D; Que, Florencia G; Nagorney, David M; Lee, Jeffrey E; Thompson, Geoffrey B

    2015-01-01

    Metastatic adrenocortical carcinoma (ACC) is rapidly fatal, with few options for treatment. Patients with metachronous recurrence may benefit from surgical resection. The survival benefit in patients with hematogenous metastasis at initial presentation is unknown. A review of all patients undergoing surgery (European Network for the Study of Adrenal Tumors) stage IV ACC between January 2000 and December 2012 from two referral centers was performed. Kaplan-Meier estimates were analyzed for disease-free and overall survival (OS). We identified 27 patients undergoing surgery for stage IV ACC. Metastases were present in the lung (19), liver (11), and brain (1). A complete resection (R0) was achieved in 11 patients. The median OS was improved in patients undergoing R0 versus R2 resection (860 vs. 390 days; p = 0.02). The 1- and 2-year OS was also improved in patients undergoing R0 versus R2 resection (69.9 %, 46.9 % vs. 53.0 %, 22.1 %; p = 0.02). Patients undergoing neoadjuvant therapy (eight patients) had a trend towards improved survival at 1, 2, and 5 years versus no neoadjuvant therapy (18 patients) [83.3 %, 62.5 %, 41.7 % vs. 56.8 %, 26.6 %, 8.9 %; p = 0.1]. Adjuvant therapy was associated with improved recurrence-free survival at 6 months and 1 year (67 %, 33 % vs. 40 %, 20 %; p = 0.04) but not improved OS (p = 0.63). Sex (p = 0.13), age (p = 0.95), and location of metastasis (lung, p = 0.51; liver, p = 0.67) did not correlate with OS after operative intervention. Symptoms of hormonal excess improved in 86 % of patients. Operative intervention, especially when an R0 resection can be achieved, following systemic therapy may improve outcomes, including OS, in select patients with stage IV ACC. Response to neoadjuvant chemotherapy may be of use in defining which patients may benefit from surgical intervention. Adjuvant therapy was associated with decreased recurrence but did not improve OS.

  17. Distal splenorenal shunt with partial spleen resection

    Directory of Open Access Journals (Sweden)

    Gajin Predrag

    2007-01-01

    Full Text Available Introduction: Hypersplenism is a common complication of portal hypertension. Cytopenia in hypersplenism is predominantly caused by splenomegaly. Distal splenorenal shunt (Warren with partial spleen resection is an original surgical technique that regulates cytopenia by reduction of the enlarged spleen. Objective. The aim of our study was to present the advantages of distal splenorenal shunt (Warren with partial spleen resection comparing morbidity and mortality in a group of patients treated by distal splenorenal shunt with partial spleen resection with a group of patients treated only by a distal splenorenal shunt. Method. From 1995 to 2003, 41 patients with portal hypertension were surgically treated due to hypersplenism and oesophageal varices. The first group consisted of 20 patients (11 male, mean age 42.3 years who were treated by distal splenorenal shunt with partial spleen resection. The second group consisted of 21 patients (13 male, mean age 49.4 years that were treated by distal splenorenal shunt only. All patients underwent endoscopy and assessment of oesophageal varices. The size of the spleen was evaluated by ultrasound, CT or by scintigraphy. Angiography was performed in all patients. The platelet and white blood cell count and haemoglobin level were registered. Postoperatively, we noted blood transfusion, complications and total hospital stay. Follow-up period was 12 months, with first checkup after one month. Results In the first group, only one patient had splenomegaly postoperatively (5%, while in the second group there were 13 patients with splenomegaly (68%. Before surgery, the mean platelet count in the first group was 51.6±18.3x109/l, to 118.6±25.4x109/l postoperatively. The mean platelet count in the second group was 67.6±22.8x109/l, to 87.8±32.1x109/l postoperatively. Concerning postoperative splenomegaly, statistically significant difference was noted between the first and the second group (p<0.05. Comparing the

  18. Bulk lifetime characterization of corona charged silicon wafers with high resistivity by means of microwave detected photoconductivity

    Science.gov (United States)

    Engst, C. R.; Rommel, M.; Bscheid, C.; Eisele, I.; Kutter, C.

    2017-12-01

    Minority carrier lifetime (lifetime) measurements are performed on corona-charged silicon wafers by means of Microwave Detected Photoconductivity (MDP). The corona charge is deposited on the front and back sides of oxidized wafers in order to adjust accumulation conditions. Once accumulation is established, interface recombination is suppressed and bulk lifetimes are obtained. Neither contacts nor non-CMOS compatible preparation techniques are required in order to achieve accumulation conditions, which makes the method ideally suited for inline characterization. The novel approach, termed ChargedMDP (CMDP), is used to investigate neutron transmutation doped (NTD) float zone silicon with resistivities ranging from 6.0 to 8.2 kΩ cm. The bulk properties of 150 mm NTD wafers are analyzed in detail by performing measurements of the carrier lifetime and the steady-state photoconductivity at various injection levels. The results are compared with MDP measurements of uncharged wafers as well as to the established charged microwave detected Photoconductance Decay (charge-PCD) method. Besides analyzing whole wafers, CMDP measurements are performed on oxide test-structures on a patterned wafer. Finally, the oxide properties are characterized by means of charge-PCD as well as capacitance-voltage measurements. With CMDP, average bulk lifetimes up to 33.1 ms are measured, whereby significant variations are observed among wafers, which are produced out of the same ingot but oxidized in different furnaces. The observed lifetime variations are assumed to be caused by contaminations, which are introduced during the oxidation process. The results obtained by CMDP were neither accessible by means of conventional MDP measurements of uncharged wafers nor with the established charge-PCD method.

  19. A Procedure to Determine and Correct for Transmission Line Resistances for Direct Current On-Wafer Measurements

    Science.gov (United States)

    2010-05-01

    device, such as a bipolar junction transistor ( BJT ), a metal oxide semiconductor field effect transistor (MOSFET), or a high electron mobility...VDS_mesh,IDS,[0:.05:.5],’:’); 12 List of Symbols, Abbreviations, and Acronyms BJT bipolar junction transistor DC direct current DUT device... transistor (HEMT), when measured on-wafer, may be measured using two separate power lines with ground-signal-ground (GSG) on-wafer probes. Each power

  20. Kerfless epitaxial silicon wafers with 7 ms carrier lifetimes and a wide lift-off process window

    Science.gov (United States)

    Gemmel, Catherin; Hensen, Jan; David, Lasse; Kajari-Schröder, Sarah; Brendel, Rolf

    2018-04-01

    Silicon wafers contribute significantly to the photovoltaic module cost. Kerfless silicon wafers that grow epitaxially on porous silicon (PSI) and are subsequently detached from the growth substrate are a promising lower cost drop-in replacement for standard Czochralski (Cz) wafers. However, a wide technological processing window appears to be a challenge for this process. This holds in particularly for the etching current density of the separation layer that leads to lift-off failures if it is too large or too low. Here we present kerfless PSI wafers of high electronic quality that we fabricate on weakly reorganized porous Si with etch current densities varying in a wide process window from 110 to 150 mA/cm2. We are able to detach all 17 out of 17 epitaxial wafers. All wafers exhibit charge carrier lifetimes in the range of 1.9 to 4.3 ms at an injection level of 1015 cm-3 without additional high-temperature treatment. We find even higher lifetimes in the range of 4.6 to 7.0 ms after applying phosphorous gettering. These results indicate that a weak reorganization of the porous layer can be beneficial for a large lift-off process window while still allowing for high carrier lifetimes.

  1. CMOS-analogous wafer-scale nanotube-on-insulator approach for submicrometer devices and integrated circuits using aligned nanotubes.

    Science.gov (United States)

    Ryu, Koungmin; Badmaev, Alexander; Wang, Chuan; Lin, Albert; Patil, Nishant; Gomez, Lewis; Kumar, Akshay; Mitra, Subhasish; Wong, H-S Philip; Zhou, Chongwu

    2009-01-01

    Massive aligned carbon nanotubes hold great potential but also face significant integration/assembly challenges for future beyond-silicon nanoelectronics. We report a wafer-scale processing of aligned nanotube devices and integrated circuits, including progress on essential technological components such as wafer-scale synthesis of aligned nanotubes, wafer-scale transfer of nanotubes to silicon wafers, metallic nanotube removal and chemical doping, and defect-tolerant integrated nanotube circuits. We have achieved synthesis of massive aligned nanotubes on complete 4 in. quartz and sapphire substrates, which were then transferred to 4 in. Si/SiO(2) wafers. CMOS analogous fabrication was performed to yield transistors and circuits with features down to 0.5 mum, with high current density approximately 20 muA/mum and good on/off ratios. In addition, chemical doping has been used to build fully integrated complementary inverter with a gain approximately 5, and a defect-tolerant design has been employed for NAND and NOR gates. This full-wafer approach could serve as a critical foundation for future integrated nanotube circuits.

  2. Detection of trace contamination of copper on a silicon wafer with TXRF

    International Nuclear Information System (INIS)

    Yamada, T.; Matsuo, M.; Kohno, H.; Mori, Y.

    2000-01-01

    The element copper on silicon wafers is one of the most important metals to be detected among the contamination in semiconductor industries. When W-Lβ 1 (9.67 keV) line is used for the excitation in TXRF instrument and when Si(Li) is used as its detector, an escape peak appears at 7.93 keV which is close to the energy of Cu-Kα line(8.04 keV). When the concentration of copper is lower than 10 10 atoms/cm 2 , accurate quantitative analysis is difficult because of the overlapping of the peaks. When Au-Lβ 1 line(11.44 keV) is used for the excitation, the escape peak appears at 9.70 keV which is far enough from the energy of Cu-Ka line. We prepared silicon wafers intentionally contaminated with copper in a low concentration range of 10 8 to 10 10 atoms/cm 2 and measured them with a TXRF instrument having Au-Lβ 1 line for excitation. The contaminated samples were made with IAP method and their Cu concentrations were calibrated with VPD-AAS method (recovery solution: 2 % HF + 2 % H 2 O 2 ). A figure shows the correlation between the results with TXRF and those with AAS. The horizontal axis is the value of concentration decided by AAS and the vertical axis is the intensity of Cu-Kα line measured with the TXRF. Six wafers of different concentration were used and five points on each wafer including the center were measured with TXRF. Five points at each concentration in the figure correspond to the results measured on one wafer. Intensities of Cu-Kα line are weak in these low concentration ranges but the background of them are also very small (less than 0.05 cps). Therefore the peak of Cu-Kα line can be distinguished from the background. It can be said that a calibration curve can be drawn to the middle range of 10 9 atoms/cm 2 . The same samples were measured with another TXRF instrument having W-Lβ 1 line for excitation. It was difficult to draw a calibration curve in this case. We will present both results taken with Au-Lβ 1 line and with W-Lβ 1 line. (author)

  3. Urethral strictures after bipolar transurethral resection of prostate may be linked to slow resection rate

    Directory of Open Access Journals (Sweden)

    Guan Hee Tan

    2017-05-01

    Full Text Available Purpose: This study aimed to determine the urethral stricture (US rate and identify clinical and surgical risk factors associated with US occurrence after transurethral resection of the prostate using the bipolar Gyrus PlasmaKinetic Tissue Management System (PKTURP. Materials and Methods: This was an age-matched case-control study of US occurrence after PK-TURP. Retrospective data were collected from the hospital records of patients who had a minimum of 36 months of follow-up information. Among the data collected for analysis were prostate-specific antigen level, estimated prostate weight, the amount of prostate resected, operative time, history of urinary tract infection, previous transurethral resection of the prostate, and whether the PK-TURP was combined with other endourological procedures. The resection rate was calculated from the collected data. Univariate and multivariate analyses were performed to identify clinical and surgical risk factors related to US formation. Results: A total of 373 patients underwent PK-TURP between 2003 and 2009. There were 13 cases of US (3.5%, and most of them (10 of 13, 76.9% presented within 24 months of surgery. Most of the US cases (11 of 13, 84.6% occurred at the bulbar urethra. Multivariable logistic regression analyses identified slow resection rate as the only risk factor significantly associated with US occurrence. Conclusions: The US rate of 3.5% after PK-TURP in this study is comparable to contemporary series. A slow resection rate seems to be related to US occurrence. This should be confirmed by further studies; meanwhile, we must be mindful of this possibility when operating with the PK-TURP system.

  4. Safety of Simultaneous Bilateral Pulmonary Resection for Metastatic Lung Tumors.

    Science.gov (United States)

    Matsubara, Taichi; Toyokawa, Gouji; Kinoshita, Fumihiko; Haratake, Naoki; Kozuma, Yuka; Akamine, Takaki; Takamori, Shinkichi; Hirai, Fumihiko; Tagawa, Tetsuzo; Okamoto, Tatsuro; Maehara, Yoshihiko

    2018-03-01

    We investigated the safety of simultaneous bilateral lung resection for lung metastases. We retrospectively analyzed 185 patients with pulmonary metastases who underwent unilateral or bilateral pulmonary resection from August 2009 to December 2016 at a single institution. Single-stage bilateral lung resection was undertaken in 19 patients, and the other 166 patients underwent unilateral pulmonary resection, including 20 patients who underwent repeated resections for synchronous or metachronous metastases. Operative time and drainage days in the bilateral group were significantly longer than those in the unilateral group (220±20 vs. 152±6.9 min: ppulmonary metastasectomy appears to be safe as long as only wedge resection is performed on at least one side. Copyright© 2018, International Institute of Anticancer Research (Dr. George J. Delinasios), All rights reserved.

  5. Treatment Strategy after Incomplete Endoscopic Resection of Early Gastric Cancer

    Science.gov (United States)

    Kim, Sang Gyun

    2016-01-01

    Endoscopic resection of early gastric cancer is defined as incomplete when tumor cells are found at the resection margin upon histopathological examination. However, a tumor-positive resection margin does not always indicate residual tumor; it can also be caused by tissue contraction during fixation, by the cautery effect during endoscopic resection, or by incorrect histopathological mapping. Cases of highly suspicious residual tumor require additional endoscopic or surgical resection. For inoperable patients, argon plasma coagulation can be used as an alternative endoscopic treatment. Immediately after the incomplete resection or residual tumor has been confirmed by the pathologist, clinicians should also decide upon any additional treatment to be carried out during the follow-up period. PMID:27435699

  6. Elevator Muscle Anterior Resection: A New Technique for Blepharoptosis.

    Science.gov (United States)

    Zigiotti, Gian Luigi; Delia, Gabriele; Grenga, Pierluigi; Pichi, Francesco; Rechichi, Miguel; Jaroudi, Mahmoud O; d'Alcontres, Francesco Stagno; Lupo, Flavia; Meduri, Alessandro

    2016-01-01

    Blepharoptosis is a condition of inadequate upper eyelid position, with a downward displacement of the upper eyelid margin resulting in obstruction of the superior visual field. Levator resection is an effective technique that is routinely used to correct aponeurotic ptosis. The anterior levator resection is the procedure of choice in moderate blepharoptosis when there is moderate to good levator muscle function, furthermore, with an anterior approach, a greater resection can be achieved than by a conjunctival approach. The authors describe a modification in the Putterman technique with a resection done over a plicated elevator, plication that was suggested by Mustardè. The technique has been named as elevator muscle anterior resection. The elevator muscle anterior resection inspires from the Fasanella-Servat operation by the use of a clamp, making the operation simple and predictable.

  7. Tracheal resection and anastomosis in dogs.

    Science.gov (United States)

    Lau, R E; Schwartz, A; Buergelt, C D

    1980-01-15

    Resection and end-to-end anastomosis of the trachea is a practical procedure for the correction of various forms of tracheal stenosis. Preplacing retention sutures facilitates manipulation of the trachea and rapid apposition of the tracheal ends. These same sutures then relieve tension on the primary suture line, assuring early epithelialization. Two dogs with tracheal stenosis were treated by use of this technique. Slight narrowing of the trachea was evident postoperatively in both dogs, but neither dyspnea nor coughing occurred during the follow-up period.

  8. Harlequin Syndrome Following Resection of Mediastinal Ganglioneuroma

    Directory of Open Access Journals (Sweden)

    Yeong Jeong Jeon

    2017-04-01

    Full Text Available Harlequin syndrome is a rare disorder of the sympathetic nervous system characterized by unilateral facial flushing and sweating. Although its etiology is unknown, this syndrome appears to be a dysfunction of the autonomic nervous system. To the best of our knowledge, thus far, very few reports on perioperative Harlequin syndrome after thoracic surgery have been published in the thoracic surgical literature. Here, we present the case of a 6-year-old patient who developed this unusual syndrome following the resection of a posterior mediastinal mass.

  9. [Resection margins in conservative breast cancer surgery].

    Science.gov (United States)

    Medina Fernández, Francisco Javier; Ayllón Terán, María Dolores; Lombardo Galera, María Sagrario; Rioja Torres, Pilar; Bascuñana Estudillo, Guillermo; Rufián Peña, Sebastián

    2013-01-01

    Conservative breast cancer surgery is facing a new problem: the potential tumour involvement of resection margins. This eventuality has been closely and negatively associated with disease-free survival. Various factors may influence the likelihood of margins being affected, mostly related to the characteristics of the tumour, patient or surgical technique. In the last decade, many studies have attempted to find predictive factors for margin involvement. However, it is currently the new techniques used in the study of margins and tumour localisation that are significantly reducing reoperations in conservative breast cancer surgery. Copyright © 2012 AEC. Published by Elsevier Espana. All rights reserved.

  10. Paraneoplastic pemphigus regression after thymoma resection

    Directory of Open Access Journals (Sweden)

    Stergiou Eleni

    2008-08-01

    Full Text Available Abstract Background Among human neoplasms thymomas are associated with highest frequency with paraneoplastic autoimmune diseases. Case presentation A case of a 42-year-old woman with paraneoplastic pemphigus as the first manifestation of thymoma is reported. Transsternal complete thymoma resection achieved pemphigus regression. The clinical correlations between pemphigus and thymoma are presented. Conclusion Our case report provides further evidence for the important role of autoantibodies in the pathogenesis of paraneoplastic skin diseases in thymoma patients. It also documents the improvement of the associated pemphigus after radical treatment of the thymoma.

  11. Curative resection of transverse colon cancer via minilaparotomy.

    Science.gov (United States)

    Ishida, Hideyuki; Ishiguro, Tohru; Ishibashi, Keiichiro; Ohsawa, Tomonori; Okada, Norimichi; Kumamoto, Kensuke; Haga, Norihiro

    2011-01-01

    Minilaparotomy has been reported to be a minimally invasive alternative to laparoscopically assisted surgery. We retrospectively evaluated the usefulness of minilaparotomy for the resection of transverse colon cancer, which has generally been considered difficult to resect laparoscopically. Patients for whom curative resection was attempted for transverse colon cancer (n = 21) or sigmoid colon cancer (n = 81) via minilaparotomy (skin incision, transverse colon cancer as well as those with sigmoid colon cancer.

  12. Colonoscopic resection of lateral spreading tumours: a prospective analysis of endoscopic mucosal resection

    OpenAIRE

    Hurlstone, D P; Sanders, D S; Cross, S S; Adam, I; Shorthouse, A J; Brown, S; Drew, K; Lobo, A J

    2004-01-01

    Background: Lateral spreading tumours are superficial spreading neoplasms now increasingly diagnosed using chromoscopic colonoscopy. The clinicopathological features and safety of endoscopic mucosal resection for lateral spreading tumours (G-type “aggregate” and F-type “flat”) has yet to be clarified in Western cohorts.

  13. Local resection of the stomach for gastric cancer.

    Science.gov (United States)

    Kinami, Shinichi; Funaki, Hiroshi; Fujita, Hideto; Nakano, Yasuharu; Ueda, Nobuhiko; Kosaka, Takeo

    2017-06-01

    The local resection of the stomach is an ideal method for preventing postoperative symptoms. There are various procedures for performing local resection, such as the laparoscopic lesion lifting method, non-touch lesion lifting method, endoscopic full-thickness resection, and laparoscopic endoscopic cooperative surgery. After the invention and widespread use of endoscopic submucosal dissection, local resection has become outdated as a curative surgical technique for gastric cancer. Nevertheless, local resection of the stomach in the treatment of gastric cancer in now expected to make a comeback with the clinical use of sentinel node navigation surgery. However, there are many issues associated with local resection for gastric cancer, other than the normal indications. These include gastric deformation, functional impairment, ensuring a safe surgical margin, the possibility of inducing peritoneal dissemination, and the associated increase in the risk of metachronous gastric cancer. In view of these issues, there is a tendency to regard local resection as an investigative treatment, to be applied only in carefully selected cases. The ideal model for local resection of the stomach for gastric cancer would be a combination of endoscopic full-thickness resection of the stomach using an ESD device and hand sutured closure using a laparoscope or a surgical robot, for achieving both oncological safety and preserved functions.

  14. Proximal fibula resection in the treatment of bone tumours.

    Science.gov (United States)

    Dieckmann, Ralf; Gebert, Carsten; Streitbürger, Arne; Henrichs, Marcel-Philipp; Dirksen, Uta; Rödl, Robert; Gosheger, Georg; Hardes, Jendrik

    2011-11-01

    We present a large study of patients with proximal fibula resection. Moreover we describe a new classification system for tumour resection of the proximal fibula independent of the tumour differentiation. In 57 patients the functional and clinical outcomes were evaluated. The follow-up ranged between six months and 22.2 years (median 7.2 years). The indication for surgery was benign tumours in ten cases and malignant tumours in 47 cases. In 13 of 45 patients, where a resection of the lateral ligament complex was done, knee instability occurred. In 32 patients a resection of the peroneal nerve with resulting peroneal palsy was necessary. Patients with peroneal resection had significantly worse functional outcome than patients without peroneal resection. An ankle foot orthosis was tolerated well by these patients. Three of four patients with pathological tibia fracture had local radiation therapy. There was no higher risk of tibia fracture in patients with partial tibial resection. Resection of tumours in the proximal fibula can cause knee instability, peroneal palsy and in cases of local radiation therapy, a higher risk of delayed wound healing and fracture. Despite the risks of proximal fibula resection, good functional results can be achieved.

  15. Cheledochal cyst resection and laparoscopic hepaticoduodenostomy

    Directory of Open Access Journals (Sweden)

    Jiménez Urueta Pedro Salvador

    2014-07-01

    Full Text Available Background. Choledochal cyst is a rare abnormality. Its esti- mated incidence is of 1:100,000 to 150,000 live births. Todani et al. in 1981 reported the main objection for performing a simpler procedure, i.e., hepaticoduodenostomy, has been the risk of an “ascending cholangitis”. This hazard, however, seems to be exaggerated. Methods: A laparoscopic procedure was performed in 8 consecutive patients with choledochal cyst between January 2010 and Septem- ber 2012; 6 females and 2 males mean age was 8 years. Results. Abdominal pain was the main symptom in everyone, jaundice in 1 patient and a palpable mass in 3 patients. Lapa- roscopic surgical treatment was complete resection of the cyst with cholecystectomy and hepaticoduodenostomy laparoscopy in every patient. Discussion and conclusion. A laparoscopic approach to chole- dochal cyst resection and hepaticoduodenostomy is feasible and safe. The hepaticoduodenal anastomosis may confer additional benefits over hepaticojejunostomy in the setting of a laparoscopic approach. The creation of a single anastomosis can decrease operative time and anesthetic exposure.

  16. Tissue Remodelling following Resection of Porcine Liver

    Directory of Open Access Journals (Sweden)

    Ingvild Engdal Nygård

    2015-01-01

    Full Text Available Aim. To study genes regulating the extracellular matrix (ECM and investigate the tissue remodelling following liver resection in porcine. Methods. Four pigs with 60% partial hepatectomy- (PHx- induced liver regeneration were studied over six weeks. Four pigs underwent sham surgery and another four pigs were used as controls of the normal liver growth. Liver biopsies were taken upon laparotomy, after three and six weeks. Gene expression profiles were obtained using porcine-specific oligonucleotide microarrays. Immunohistochemical staining was performed and a proliferative index was assessed. Results. More differentially expressed genes were associated with the regulation of ECM in the resection group compared to the sham and control groups. Secreted protein acidic and rich in cysteine (SPARC and collagen 1, alpha 2 (COL1A2 were both upregulated in the early phase of liver regeneration, validated by immunopositive cells during the remodelling phase of liver regeneration. A broadened connective tissue was demonstrated by Masson’s Trichrome staining, and an immunohistochemical staining against pan-Cytokeratin (pan-CK demonstrated a distinct pattern of migrating cells, followed by proliferating cell nuclear antigen (PCNA positive nuclei. Conclusions. The present study demonstrates both a distinct pattern of PCNA positive nuclei and a deposition of ECM proteins in the remodelling phase of liver regeneration.

  17. Enhanced recovery after surgery in gastric resections.

    Science.gov (United States)

    Bruna Esteban, Marcos; Vorwald, Peter; Ortega Lucea, Sonia; Ramírez Rodríguez, Jose Manuel

    2017-02-01

    Enhanced recovery after surgery is a modality of perioperative management with the purpose of improving results and providing a faster recovery of patients. This kind of protocol has been applied frequently in colorectal surgery, presenting less available experience and evidence in gastric surgery. According to the RICA guidelines published in 2015, a review of the bibliography and the consensus established in a multidisciplinary meeting in Zaragoza on the 9th of October 2015, we present a protocol that contains the basic procedures of fast-track for resective gastric surgery. The measures to be applied are divided in a preoperative, perioperative and postoperative stage. This document provides recommendations concerning the appropriate information, limited fasting and administration of carbohydrate drinks 2hours before surgery, specialized anesthetic strategies, minimal invasive surgery, no routine use of drainages and tubes, mobilization and early oral tolerance during the immediate postoperative period, as well as criteria for discharge. The application of a protocol of enhanced recovery after surgery in resective gastric surgery can improve and accelerate the functional recovery of our patients, requiring an appropriate multidisciplinary coordination, the evaluation of obtained results with the application of these measures and the investigation of controversial topics about which we currently have limited evidence. Copyright © 2016 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  18. Comparative study on the predictability of statistical models (RSM and ANN) on the behavior of optimized buccoadhesive wafers containing Loratadine and their in vivo assessment.

    Science.gov (United States)

    Chakraborty, Prithviraj; Parcha, Versha; Chakraborty, Debarupa D; Ghosh, Amitava

    2016-01-01

    Buccoadhesive wafer dosage form containing Loratadine is formulated utilizing Formulation by Design (FbD) approach incorporating sodium alginate and lactose monohydrate as independent variable employing solvent casting method. The wafers were statistically optimized using Response Surface Methodology (RSM) and Artificial Neural Network algorithm (ANN) for predicting physicochemical and physico-mechanical properties of the wafers as responses. Morphologically wafers were tested using SEM. Quick disintegration of the samples was examined employing Optical Contact Angle (OCA). The comparison of the predictability of RSM and ANN showed a high prognostic capacity of RSM model over ANN model in forecasting mechanical and physicochemical properties of the wafers. The in vivo assessment of the optimized buccoadhesive wafer exhibits marked increase in bioavailability justifying the administration of Loratadine through buccal route, bypassing hepatic first pass metabolism.

  19. Integrated optical MEMS using through-wafer vias and bump-bonding.

    Energy Technology Data Exchange (ETDEWEB)

    McCormick, Frederick Bossert; Frederick, Scott K.

    2008-01-01

    This LDRD began as a three year program to integrate through-wafer vias, micro-mirrors and control electronics with high-voltage capability to yield a 64 by 64 array of individually controllable micro-mirrors on 125 or 250 micron pitch with piston, tip and tilt movement. The effort was a mix of R&D and application. Care was taken to create SUMMiT{trademark} (Sandia's ultraplanar, multilevel MEMS technology) compatible via and mirror processes, and the ultimate goal was to mate this MEMS fabrication product to a complementary metal-oxide semiconductor (CMOS) electronics substrate. Significant progress was made on the via and mirror fabrication and design, the attach process development as well as the electronics high voltage (30 volt) and control designs. After approximately 22 months, the program was ready to proceed with fabrication and integration of the electronics, final mirror array, and through wafer vias to create a high resolution OMEMS array with individual mirror electronic control. At this point, however, mission alignment and budget constraints reduced the last year program funding and redirected the program to help support the through-silicon via work in the Hyper-Temporal Sensors (HTS) Grand Challenge (GC) LDRD. Several months of investigation and discussion with the HTS team resulted in a revised plan for the remaining 10 months of the program. We planned to build a capability in finer-pitched via fabrication on thinned substrates along with metallization schemes and bonding techniques for very large arrays of high density interconnects (up to 2000 x 2000 vias). Through this program, Sandia was able to build capability in several different conductive through wafer via processes using internal and external resources, MEMS mirror design and fabrication, various bonding techniques for arrayed substrates, and arrayed electronics control design with high voltage capability.

  20. An electret-based energy harvesting device with a wafer-level fabrication process

    DEFF Research Database (Denmark)

    Crovetto, Andrea; Wang, Fei; Hansen, Ole

    2013-01-01

    This paper presents a MEMS energy harvesting device which is able to generate power from two perpendicular ambient vibration directions. A CYTOP polymer is used both as the electret material for electrostatic transduction and as a bonding interface for low-temperature wafer bonding. The device...... is also discussed. With a final chip size of about 1 cm2, a power output of 32.5 nW is successfully harvested with an external load of 17 MΩ, when a harmonic vibration source with an RMS acceleration amplitude of 0.03 g (∼0.3 m s−2) and a resonant frequency of 179 Hz is applied. These results can...

  1. Magnetic structure of cross-shaped permalloy arrays embedded in silicon wafers

    International Nuclear Information System (INIS)

    Machida, Kenji; Tezuka, Tomoyuki; Yamamoto, Takahiro; Ishibashi, Takayuki; Morishita, Yoshitaka; Koukitu, Akinori; Sato, Katsuaki

    2005-01-01

    This paper describes the observed magnetic structure and the micromagnetic simulation of cross-shaped, permalloy (Ni 80 Fe 20 ) arrays embedded in silicon wafers. The nano-scale-width, cross-shaped patterns were fabricated using the damascene technique, electron beam lithography, and chemical mechanical polishing. The magnetic poles were observed as two pairs of bright and dark spots at the ends of the crossed-bars using a magnetic force microscope. The force gradient distributions were simulated based on micromagnetic calculations and tip's stray field calculations using the integral equation method. This process of calculation successfully explains the appearance of the poles and complicated spin structure at the crossing region

  2. Production planning and control for semiconductor wafer fabrication facilities modeling, analysis, and systems

    CERN Document Server

    Mönch, Lars; Mason, Scott J

    2012-01-01

    Over the last fifty-plus years, the increased complexity and speed of integrated circuits have radically changed our world. Today, semiconductor manufacturing is perhaps the most important segment of the global manufacturing sector. As the semiconductor industry has become more competitive, improving planning and control has become a key factor for business success. This book is devoted to production planning and control problems in semiconductor wafer fabrication facilities. It is the first book that takes a comprehensive look at the role of modeling, analysis, and related information systems

  3. Productivity Improvement for the SHX--SEN's Single-Wafer High-Current Ion Implanter

    International Nuclear Information System (INIS)

    Ninomiya, Shiro; Ochi, Akihiro; Kimura, Yasuhiko; Yumiyama, Toshio; Kudo, Tetsuya; Kurose, Takeshi; Kariya, Hiroyuki; Tsukihara, Mitsukuni; Ishikawa, Koji; Ueno, Kazuyoshi

    2011-01-01

    Equipment productivity is a critical issue for device fabrication. For ion implantation, productivity is determined both by ion current at the wafer and by utilization efficiency of the ion beam. Such improvements not only result in higher fabrication efficiency but also reduce consumption of both electrical power and process gases. For high-current ion implanters, reduction of implant area is a key factor to increase efficiency. SEN has developed the SAVING system (Scanning Area Variation Implantation with Narrower Geometrical pattern) to address this opportunity. In this paper, three variations of the SAVING system are introduced along with discussion of their effects on fab productivity.

  4. Wafer level hermetic packaging based on Cu-Sn isothermal solidification technology

    International Nuclear Information System (INIS)

    Cao Yuhan; Luo Le

    2009-01-01

    A novel wafer level bonding method based on Cu-Sn isothermal solidification technology is established. A multi-layer sealing ring and the bonding processing are designed, and the amount of solder and the bonding parameters are optimized based on both theoretical and experimental results. Verification shows that oxidation of the solder layer, voids and the scalloped-edge appearance of the Cu 6 Sn 5 phase are successfully avoided. An average shear strength of 19.5 MPa and an excellent leak rate of around 1.9 x 10 -9 atm cc/s are possible, meeting the demands of MIL-STD-883E. (semiconductor technology)

  5. Penggunaan Limbah Kopi Sebagai Bahan Penyusun Ransum Itik Peking dalam Bentuk Wafer Ransum Komplit

    OpenAIRE

    Muhammad Daud; Zahrul Fuadi; Sultana Sultana

    2013-01-01

    Effect of coffee waste as component of compiler ration peking duck in the form of wafer complete ration ABSTRACT. Coffee waste is a by-product of coffee processing that potential to be used as feed stuff for peking duck. The weakness of this coffee waste, among others, is perishable, voluminous (bulky) and the availability was fluctuated so the processing technology is needed to make this vegetable waste to be durable, easy to stored and to be given to livestock. To solve this problem veg...

  6. Room temperature wafer direct bonding of smooth Si surfaces recovered by Ne beam surface treatments

    Science.gov (United States)

    Kurashima, Yuichi; Maeda, Atsuhiko; Takagi, Hideki

    2013-06-01

    We examined the applicability of a Ne fast atom beam (FAB) to surface activated bonding of Si wafers at room temperature. With etching depth more than 1.5 nm, the bonding strength comparable to Si bulk strength was attained. Moreover, we found the improvement of the bonding strength by surface smoothing effect of the Ne FAB. Silicon surface roughness decreased from 0.40 to 0.17 nm rms by applying a Ne FAB of 30 nm etching depth. The bonding strength between surfaces recovered by Ne FAB surface smoothing was largely improved and finally became equivalent to Si bulk strength.

  7. Microsized structures assisted nanostructure formation on ZnSe wafer by femtosecond laser irradiation

    International Nuclear Information System (INIS)

    Wang, Shutong; Feng, Guoying; Zhou, Shouhuan

    2014-01-01

    Micro/nano patterning of ZnSe wafer is demonstrated by femtosecond laser irradiation through a diffracting pinhole. The irradiation results obtained at fluences above the ablation threshold are characterized by scanning electron microscopy. The microsized structure with low spatial frequency has a good agreement with Fresnel diffraction theory. Laser induced periodic surface structures and laser-induced periodic curvelet surface structures with high spatial frequency have been found on the surfaces of microsized structures, such as spikes and valleys. We interpret its formation in terms of the interference between the reflected laser field on the surface of the valley and the incident laser pulse

  8. Dislocation sources and slip band nucleation from indents on silicon wafers

    International Nuclear Information System (INIS)

    Wittge, J.; Danilewsky, A.N.; Allen, D.

    2010-01-01

    The nucleation of dislocations at controlled indents in silicon during rapid thermal annealing has been studied by in situ X-ray diffraction imaging (topography). Concentric loops extending over pairs of inclined {111} planes were formed, the velocities of the inclined and parallel segments being almost equal. Following loss of the screw segment from the wafer, the velocity of the inclined segments almost doubled, owing to removal of the line tension of the screw segments. The loops acted as obstacles to slip band propagation. (orig.)

  9. Nanodiamond resonators fabricated on 8″ Si substrates using adhesive wafer bonding

    Science.gov (United States)

    Lebedev, V.; Lisec, T.; Yoshikawa, T.; Reusch, M.; Iankov, D.; Giese, C.; Žukauskaitė, A.; Cimalla, V.; Ambacher, O.

    2017-06-01

    In this work, the adhesive wafer bonding of diamond thin films onto 8″ silicon substrates is reported. In order to characterize bonded nano-crystalline diamond layers, vibrometry and interferometry studies of micro-fabricated flexural beam and disk resonators were carried out. In particular, surface topology along with resonant frequencies, eigenmodes and mechanical quality factors were recorded and analyzed in order to obtain physical parameters of the transferred films. The vibration properties of the bonded resonators were compared to those fabricated directly on 3″ silicon substrates.

  10. Mathematical Description of Wafer-1, a Three-Dimensional Code for LWR Fuel Performance Analysis

    DEFF Research Database (Denmark)

    Kjær-Pedersen, Niels

    1975-01-01

    This article describes in detail the mathematical formulation used in the WAFER-1 code, which is presently used for three-dimensional analysis of LWR fuel pin performance. The code aims at a prediction of the local stress-strain history in the cladding, especially with regard to the ridging...... phenomenon. To achieve this, a clad model based on shell theory has been developed. This model interacts with a detailed finite difference pellet model which treats radial and transversal cracking in the pellet in a deterministic way, based on certain assumptions with respect to the cracking pattern. Pellet...

  11. Duodenal endoscopic full-thickness resection (with video).

    Science.gov (United States)

    Schmidt, Arthur; Meier, Benjamin; Cahyadi, Oscar; Caca, Karel

    2015-10-01

    Endoscopic resection of duodenal non-lifting adenomas and subepithelial tumors is challenging and harbors a significant risk of adverse events. We report on a novel technique for duodenal endoscopic full-thickness resection (EFTR) by using an over-the-scope device. Data of 4 consecutive patients who underwent duodenal EFTR were analyzed retrospectively. Main outcome measures were technical success, R0 resection, histologic confirmation of full-thickness resection, and adverse events. Resections were done with a novel, over-the-scope device (full-thickness resection device, FTRD). Four patients (median age 60 years) with non-lifting adenomas (2 patients) or subepithelial tumors (2 patients) underwent EFTR in the duodenum. All lesions could be resected successfully. Mean procedure time was 67.5 minutes (range 50-85 minutes). Minor bleeding was observed in 2 cases; blood transfusions were not required. There was no immediate or delayed perforation. Mean diameter of the resection specimen was 28.3 mm (range 22-40 mm). Histology confirmed complete (R0) full-thickness resection in 3 of 4 cases. To date, 2-month endoscopic follow-up has been obtained in 3 patients. In all cases, the over-the-scope clip was still in place and could be removed without adverse events; recurrences were not observed. EFTR in the duodenum with the FTRD is a promising technique that has the potential to spare surgical resections. Modifications of the device should be made to facilitate introduction by mouth. Prospective studies are needed to further evaluate efficacy and safety for duodenal resections. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

  12. Laparoscopic versus open resection for sigmoid diverticulitis.

    Science.gov (United States)

    Abraha, Iosief; Binda, Gian A; Montedori, Alessandro; Arezzo, Alberto; Cirocchi, Roberto

    2017-11-25

    Diverticular disease is a common condition in Western industrialised countries. Most individuals remain asymptomatic throughout life; however, 25% experience acute diverticulitis. The standard treatment for acute diverticulitis is open surgery. Laparoscopic surgery - a minimal-access procedure - offers an alternative approach to open surgery, as it is characterised by reduced operative stress that may translate into shorter hospitalisation and more rapid recovery, as well as improved quality of life. To evaluate the effectiveness of laparoscopic surgical resection compared with open surgical resection for individuals with acute sigmoid diverticulitis. We searched the following electronic databases: the Cochrane Central Register of Controlled Trials (CENTRAL; 2017, Issue 2) in the Cochrane Library; Ovid MEDLINE (1946 to 23 February 2017); Ovid Embase (1974 to 23 February 2017); clinicaltrials.gov (February 2017); and the World Health Organization (WHO) International Clinical Trials Registry (February 2017). We reviewed the bibliographies of identified trials to search for additional studies. We included randomised controlled trials comparing elective or emergency laparoscopic sigmoid resection versus open surgical resection for acute sigmoid diverticulitis. Two review authors independently selected studies, assessed the domains of risk of bias from each included trial, and extracted data. For dichotomous outcomes, we calculated risk ratios (RRs) with 95% confidence intervals (CIs). For continuous outcomes, we planned to calculate mean differences (MDs) with 95% CIs for outcomes such as hospital stay, and standardised mean differences (SMDs) with 95% CIs for quality of life and global rating scales, if researchers used different scales. Three trials with 392 participants met the inclusion criteria. Studies were conducted in three European countries (Switzerland, Netherlands, and Germany). The median age of participants ranged from 62 to 66 years; 53% to 64% were

  13. Improvements to the solar cell efficiency and production yields of low-lifetime wafers with effective phosphorus gettering

    International Nuclear Information System (INIS)

    Lu, Jiunn-Chenn; Chen, Ping-Nan; Chen, Chih-Min; Wu, Chung-Han

    2013-01-01

    Highlights: • Variable-temperature gettering improves efficiencies when the wafer quality is poor. • High-quality wafers need not be used for variable-temperature gettering. • The proposed gettering method is based on an existing diffusion process. • It has a potential interest for hot-spot prevention. -- Abstract: This research focuses on the improvement of solar cell efficiencies in low-lifetime wafers by implementing an appropriate gettering method of the diffusion process. The study also considers a reduction in the value of the reverse current at −12 V, an important electrical parameter related to the hot-spot heating of solar cells and modules, to improve the product's quality during commercial mass production. A practical solar cell production case study is examined to illustrate the use of the proposed method. The results of this case study indicate that variable-temperature gettering significantly improves solar cell efficiencies by 0.14% compared to constant-temperature methods when the wafer quality is poor. Moreover, this study finds that variable-temperature gettering raises production yields of low quality wafers by more than 30% by restraining the measurement value of the reverse current at −12 V during solar cell manufacturing

  14. Wafer bowing control of free-standing heteroepitaxial diamond (100) films grown on Ir(100) substrates via patterned nucleation growth

    International Nuclear Information System (INIS)

    Yoshikawa, Taro; Kodama, Hideyuki; Kono, Shozo; Suzuki, Kazuhiro; Sawabe, Atsuhito

    2015-01-01

    The potential of patterned nucleation growth (PNG) technique to control the wafer bowing of free-standing heteroepitaxial diamond films was investigated. The heteroepitaxial diamond (100) films were grown on an Ir(100) substrate via PNG technique with different patterns of nucleation regions (NRs), which were dot-arrays with 8 or 13 μm pitch aligned to < 100 > or < 110 > direction of the Ir(100) substrate. The wafer bows and the local stress distributions of the free-standing films were measured using a confocal micro-Raman spectrometer. For each NR pattern, the stress evolutions within the early stage of diamond growth were also studied together with a scanning electron microscopic observation of the coalescing diamond particles. These investigations revealed that the NR pattern, in terms of pitch and direction of dot-array, strongly affects the compressive stress on the nucleation side of the diamond film and dominantly contributes to the elastic deformation of the free-standing film. This indicates that the PNG technique with an appropriate NR pattern is a promising solution to fabricate free-standing heteroepitaxial diamond films with extremely small bows. - Highlights: • Wafer bowing control of free-standing heteroepitaxial diamond (100) films • Effect of patterned nucleation and growth (PNG) technique on wafer bowing reduction • Influence of nucleation region patterns of PNG on wafer bowing • Internal stress analysis of PNG films via confocal micro-Raman spectroscopy

  15. In-situ wafer bowing measurements of GaN grown on Si (111) substrate by reflectivity mapping in metal organic chemical vapor deposition system

    International Nuclear Information System (INIS)

    Yang Yi-Bin; Liu Ming-Gang; Chen Wei-Jie; Han Xiao-Biao; Chen Jie; Lin Xiu-Qi; Lin Jia-Li; Luo Hui; Liao Qiang; Zang Wen-Jie; Chen Yin-Song; Qiu Yun-Ling; Wu Zhi-Sheng; Liu Yang; Zhang Bai-Jun

    2015-01-01

    In this work, the wafer bowing during growth can be in-situ measured by a reflectivity mapping method in the 3×2″ Thomas Swan close coupled showerhead metal organic chemical vapor deposition (MOCVD) system. The reflectivity mapping method is usually used to measure the film thickness and growth rate. The wafer bowing caused by stresses (tensile and compressive) during the epitaxial growth leads to a temperature variation at different positions on the wafer, and the lower growth temperature leads to a faster growth rate and vice versa. Therefore, the wafer bowing can be measured by analyzing the discrepancy of growth rates at different positions on the wafer. Furthermore, the wafer bowings were confirmed by the ex-situ wafer bowing measurement. High-resistivity and low-resistivity Si substrates were used for epitaxial growth. In comparison with low-resistivity Si substrate, GaN grown on high-resistivity substrate shows a larger wafer bowing caused by the highly compressive stress introduced by compositionally graded AlGaN buffer layer. This transition of wafer bowing can be clearly in-situ measured by using the reflectivity mapping method. (paper)

  16. Indications and outcome of childhood preventable bowel resections ...

    African Journals Online (AJOL)

    injury (2), gangrenous umbilical hernia (2), blunt abdominal trauma (1), midgut volvulus (1), necrotizing enterocolitis (1), strangulated inguinal hernia (1), postoperative band intestinal obstructions (1). There were 16 right hemicolectomies, 4 small bowel resections and 2 massive bowel resections. Average duration of ...

  17. Endoscopic lesions in Crohn's disease early after ileocecal resection

    NARCIS (Netherlands)

    Tytgat, G. N.; Mulder, C. J.; Brummelkamp, W. H.

    1988-01-01

    Fifty patients with Crohn's disease were studied endoscopically 6 weeks to 6 months (median 9 weeks) after ileocecal or ileocolonic resection for evidence of non-resected abnormality. Only 8 of the 50 patients were endoscopically free of abnormalities. Microscopic examination of the surgical

  18. Pancreatoduodenectomy with colon resection for cancer: A nationwide retrospective analysis

    NARCIS (Netherlands)

    Marsman, E. Madelief; de Rooij, Thijs; van Eijck, Casper H.; Boerma, Djamila; Bonsing, Bert A.; van Dam, Ronald M.; van Dieren, Susan; Erdmann, Joris I.; Gerhards, Michael F.; de Hingh, Ignace H.; Kazemier, Geert; Klaase, Joost; Molenaar, I. Quintus; Patijn, Gijs A.; Scheepers, Joris J.; Tanis, Pieter J.; Busch, Olivier R.; Besselink, Marc G.

    2016-01-01

    Microscopically radical (R0) resection of pancreatic, periampullary, or colon cancer may occasionally require a pancreatoduodenectomy with colon resection (PD-colon), but the benefits of this procedure have been disputed, and multicenter studies on morbidity and oncologic outcomes after PD-colon are

  19. Liver resection for non-cirrhotic hepatocellular carcinoma in south ...

    African Journals Online (AJOL)

    Background. We describe the clinicopathologic features and outcome of South African patients who have undergone hepatic resection for hepatocellular carcinoma (HCC) arising in a non-cirrhotic liver. Methods. We utilised the prospective liver resection database in the Surgical Gastroenterology Unit at Groote Schuur ...

  20. Transurethral resection of very large prostates. A retrospective study

    DEFF Research Database (Denmark)

    Waaddegaard, P; Hansen, B J; Christensen, S W

    1991-01-01

    Twenty-one patients with benign prostatic hypertrophy (BPH), and a weight of transurethrally resected tissue exceeding 80 g (Group 1), were compared to a control group of 30 patients with a weight of resected tissue less than 80 g (Group 2) with regard to the peri- and postoperative course...... large prostates....

  1. Non-Vascularised Fibular Grafting After Resection of Distal Femoral ...

    African Journals Online (AJOL)

    Background: Vascularized fibular grafting, allografting, megaprosthesis and allograft-prosthesis composite are suitable limb salvage techniques after resection of ... the initial observation showed such a wide non-vascularized fibular grafting for arthrodesis of the knee after resection of the distal femoral tumours is a feasible ...

  2. Incidence and management of bile leakage after partial liver resection

    NARCIS (Netherlands)

    Erdogan, D.; Busch, O. R. C.; van Delden, O. M.; Rauws, E. A. J.; Gouma, D. J.; van Gulik, T. M.

    2008-01-01

    Background/Aims: Bile leakage after partial liver resection still is a common complication and is associated with substantial morbidity and even mortality. Methods: A total of 234 consecutive liver resections without biliary reconstruction, performed between January 1992 and December 2004, were

  3. Comparison between open and arthroscopic procedure for lateral clavicle resection

    NARCIS (Netherlands)

    Duindam, N.; Kuiper, J.W.P.; Hoozemans, M.J.M.; Burger, B.J.

    2014-01-01

    Purpose: Arthroscopic lateral clavicle resection (LCR) is increasingly used, compared to an open approach, but literature does not clearly indicate which approach is preferable. The goal of this study was to compare function and pain between patients who underwent lateral clavicle resection using an

  4. Comparison of wedge resection (Winograd procedure) and wedge resection plus complete nail plate avulsion in the treatment of ingrown toenails.

    Science.gov (United States)

    Huang, Jia-Zhang; Zhang, Yi-Jun; Ma, Xin; Wang, Xu; Zhang, Chao; Chen, Li

    2015-01-01

    The present retrospective study compared the efficacy of wedge resection (Winograd procedure) and wedge resection plus complete nail plate avulsion for the treatment of ingrown toenails (onychocryptosis). Two surgical methods were performed in 95 patients with a stage 2 or 3 ingrown toenail. Each patient was examined weekly until healing and then at 1, 6, and 12 months of follow-up. The outcomes measured were surgical duration, healing time, recurrence rate, the incidence of postoperative infection, and cosmetic appearance after surgery. Of the 95 patients (115 ingrown toenails) included in the present study, 39 (41.1%) underwent wedge resection (Winograd procedure) and 56 (59%), wedge resection plus complete nail plate avulsion. The mean surgical duration for wedge resection (Winograd procedure) and wedge resection plus complete nail plate avulsion was 14.9 ± 2.4 minutes and 15.1 ± 3.2 minutes, respectively (p = .73). The corresponding healing times were 2.8 ± 1.2 weeks and 2.7 ± 1.3 weeks (p = .70). Recurrence developed in 3 (3.2%) patients after wedge resection (Winograd procedure) and in 4 (4.2%) after wedge resection plus complete nail plate avulsion. In addition, postoperative infection occurred in 3 (3.2%) patients after wedge resection (Winograd procedure) and 2 (2.1%) after wedge resection plus complete nail plate avulsion. Both of the surgical procedures were practical and appropriate for the treatment of ingrown toenails, being simple and associated with low morbidity and a high success rate. However, cosmetically, wedge resection (Winograd procedure) would be the better choice because the nail plate remains intact. Copyright © 2015 American College of Foot and Ankle Surgeons. Published by Elsevier Inc. All rights reserved.

  5. Cephalic aura after frontal lobe resection.

    Science.gov (United States)

    Kakisaka, Yosuke; Jehi, Lara; Alkawadri, Rafeed; Wang, Zhong I; Enatsu, Rei; Mosher, John C; Dubarry, Anne-Sophie; Alexopoulos, Andreas V; Burgess, Richard C

    2014-08-01

    A cephalic aura is a common sensory aura typically seen in frontal lobe epilepsy. The generation mechanism of cephalic aura is not fully understood. It is hypothesized that to generate a cephalic aura extensive cortical areas need to be excited. We report a patient who started to have cephalic aura after right frontal lobe resection. Magnetoencephalography (MEG) showed interictal spike and ictal change during cephalic aura, both of which were distributed in the right frontal region, and the latter involved much more widespread areas than the former on MEG sensors. The peculiar seizure onset pattern may indicate that surgical modification of the epileptic network was related to the appearance of cephalic aura. We hypothesize that generation of cephalic aura may be associated with more extensive cortical involvement of epileptic activity than that of interictal activity, in at least a subset of cases. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Self-consistent simulation study on magnetized inductively coupled plasma for 450 mm semiconductor wafer processing

    International Nuclear Information System (INIS)

    Lee, Ho-Jun; Kim, Yun-Gi

    2012-01-01

    The characteristics of weakly magnetized inductively coupled plasma (MICP) are investigated using a self-consistent simulation based on the drift–diffusion approximation with anisotropic transport coefficients. MICP is a plasma source utilizing the cavity mode of the low-frequency branch of the right-hand circularly polarized wave. The model system is 700 mm in diameter and has a 250 mm gap between the radio-frequency window and wafer holder. The model chamber size is chosen to verify the applicability of this type of plasma source to the 450 mm wafer process. The effects of electron density distribution and external axial magnetic field on the propagation properties of the plasma wave, including the wavelength modulation and refraction toward the high-density region, are demonstrated. The restricted electron transport and thermal conductivity in the radial direction due to the magnetic field result in small temperature gradient along the field lines and off-axis peak density profile. The calculated impedance seen from the antenna terminal shows that MICP has a resistance component that is two to threefold higher than that of ICP. This property is practically important for large-size, low-pressure plasma sources because high resistance corresponds to high power-transfer efficiency and stable impedance matching characteristics. For the 0.665 Pa argon plasma, MICP shows a radial density uniformity of 6% within 450 mm diameter, which is much better than that of nonmagnetized ICP.

  7. Digital Platform for Wafer-Level MEMS Testing and Characterization Using Electrical Response

    Directory of Open Access Journals (Sweden)

    Nuno Brito

    2016-09-01

    Full Text Available The uniqueness of microelectromechanical system (MEMS devices, with their multiphysics characteristics, presents some limitations to the borrowed test methods from traditional integrated circuits (IC manufacturing. Although some improvements have been performed, this specific area still lags behind when compared to the design and manufacturing competencies developed over the last decades by the IC industry. A complete digital solution for fast testing and characterization of inertial sensors with built-in actuation mechanisms is presented in this paper, with a fast, full-wafer test as a leading ambition. The full electrical approach and flexibility of modern hardware design technologies allow a fast adaptation for other physical domains with minimum effort. The digital system encloses a processor and the tailored signal acquisition, processing, control, and actuation hardware control modules, capable of the structure position and response analysis when subjected to controlled actuation signals in real time. The hardware performance, together with the simplicity of the sequential programming on a processor, results in a flexible and powerful tool to evaluate the newest and fastest control algorithms. The system enables measurement of resonant frequency (Fr, quality factor (Q, and pull-in voltage (Vpi within 1.5 s with repeatability better than 5 ppt (parts per thousand. A full-wafer with 420 devices under test (DUTs has been evaluated detecting the faulty devices and providing important design specification feedback to the designers.

  8. Wafer-level chip-scale packaging analog and power semiconductor applications

    CERN Document Server

    Qu, Shichun

    2015-01-01

    This book presents a state-of-art and in-depth overview in analog and power WLCSP design, material characterization, reliability, and modeling. Recent advances in analog and power electronic WLCSP packaging are presented based on the development of analog technology and power device integration. The book covers in detail how advances in semiconductor content, analog and power advanced WLCSP design, assembly, materials, and reliability have co-enabled significant advances in fan-in and fan-out with redistributed layer (RDL) of analog and power device capability during recent years. Along with new analog and power WLCSP development, the role of modeling is a key to assure successful package design. An overview of the analog and power WLCSP modeling and typical thermal, electrical, and stress modeling methodologies is also provided. This book also: ·         Covers the development of wafer-level power discrete packaging with regular wafer-level design concepts and directly bumping technology ·    �...

  9. Anodic bonding using SOI wafer for fabrication of capacitive micromachined ultrasonic transducers

    International Nuclear Information System (INIS)

    Bellaredj, M; Bourbon, G; Walter, V; Moal, P Le; Berthillier, M

    2014-01-01

    In medical ultrasound imaging, mostly piezoelectric crystals are used as ultrasonic transducers. Capacitive micromachined ultrasonic transducers (CMUTs) introduced around 1994 have been shown to be a good alternative to conventional piezoelectric transducers in various aspects, such as sensitivity, transduction efficiency or bandwidth. This paper focuses on a fabrication process for CMUTs using anodic bonding of a silicon on insulator wafer on a glass wafer. The processing steps are described leading to a good control of the mechanical response of the membrane. This technology makes possible the fabrication of large membranes and can extend the frequency range of CMUTs to lower frequencies of operation. Silicon membranes having radii of 50, 70, 100 and 150 µm and a 1.5 µm thickness are fabricated and electromechanically characterized using an auto-balanced bridge impedance analyzer. Resonant frequencies from 0.6 to 2.3 MHz and an electromechanical coupling coefficient around 55% are reported. The effects of residual stress in the membranes and uncontrolled clamping conditions are clearly responsible for the discrepancies between experimental and theoretical values of the first resonance frequency. The residual stress in the membranes is determined to be between 90 and 110 MPa. The actual boundary conditions are between the clamped condition and the simply supported condition and can be modeled with a torsional stiffness of 2.10 −7  Nm rad –1  in the numerical model. (paper)

  10. Fabrication and Characterization of Capacitive Micromachined Ultrasonic Transducers with Low-Temperature Wafer Direct Bonding

    Directory of Open Access Journals (Sweden)

    Xiaoqing Wang

    2016-12-01

    Full Text Available This paper presents a fabrication method of capacitive micromachined ultrasonic transducers (CMUTs by wafer direct bonding, which utilizes both the wet chemical and O2plasma activation processes to decrease the bonding temperature to 400 °C. Two key surface properties, the contact angle and surface roughness, are studied in relation to the activation processes, respectively. By optimizing the surface activation parameters, a surface roughness of 0.274 nm and a contact angle of 0° are achieved. The infrared images and static deflection of devices are assessed to prove the good bonding effect. CMUTs having silicon membranes with a radius of 60 μm and a thickness of 2 μm are fabricated. Device properties have been characterized by electrical and acoustic measurements to verify their functionality and thus to validate this low-temperature process. A resonant frequency of 2.06 MHz is obtained by the frequency response measurements. The electrical insertion loss and acoustic signal have been evaluated. This study demonstrates that the CMUT devices can be fabricated by low-temperature wafer direct bonding, which makes it possible to integrate them directly on top of integrated circuit (IC substrates.

  11. ASIC Wafer Test System for the ATLAS Semiconductor Tracker Front-End Chip

    Energy Technology Data Exchange (ETDEWEB)

    Anghinolfi, F.; Bialas, W.; Busek, N.; Ciocio, A.; Cosgrove, D.; Fadeyev, V.; Flacco, C.; Gilchriese, M.; Grillo, A.A.; Haber, C.; Kaplon, J.; Lacasta, C.; Murray, W.; Niggli, H.; Pritchard, T.; Rosenbaum, F.; Spieler, H.; Stezelberger, T.; Vu, C.; Wilder, M.; Yaver, H.; Zetti, F.

    2002-03-19

    An ASIC wafer test system has been developed to provide comprehensive production screening of the ATLAS Semiconductor Tracker front-end chip (ABCD3T). The ABCD3T[1] features a 128-channel analog front-end, a digital pipeline, and communication circuitry, clocked at 40 MHz, which is the bunch crossing frequency at the LHC (Large Hadron Collider). The tester measures values and tolerance ranges of all critical IC parameters, including DC parameters, electronic noise, time resolution, clock levels and clock timing. The tester is controlled by an FPGA (ORCA3T) programmed to issue the input commands to the IC and to interpret the output data. This allows the high-speed wafer-level IC testing necessary to meet the production schedule. To characterize signal amplitudes and phase margins, the tester utilizes pin-driver, delay, and DAC chips, which control the amplitudes and delays of signals sent to the IC under test. Output signals from the IC under test go through window comparator chips to measure their levels. A probe card has been designed specifically to reduce pick-up noise that can affect the measurements. The system can operate at frequencies up to 100 MHz to study the speed limits of the digital circuitry before and after radiation damage. Testing requirements and design solutions are presented.

  12. Digital Platform for Wafer-Level MEMS Testing and Characterization Using Electrical Response

    Science.gov (United States)

    Brito, Nuno; Ferreira, Carlos; Alves, Filipe; Cabral, Jorge; Gaspar, João; Monteiro, João; Rocha, Luís

    2016-01-01

    The uniqueness of microelectromechanical system (MEMS) devices, with their multiphysics characteristics, presents some limitations to the borrowed test methods from traditional integrated circuits (IC) manufacturing. Although some improvements have been performed, this specific area still lags behind when compared to the design and manufacturing competencies developed over the last decades by the IC industry. A complete digital solution for fast testing and characterization of inertial sensors with built-in actuation mechanisms is presented in this paper, with a fast, full-wafer test as a leading ambition. The full electrical approach and flexibility of modern hardware design technologies allow a fast adaptation for other physical domains with minimum effort. The digital system encloses a processor and the tailored signal acquisition, processing, control, and actuation hardware control modules, capable of the structure position and response analysis when subjected to controlled actuation signals in real time. The hardware performance, together with the simplicity of the sequential programming on a processor, results in a flexible and powerful tool to evaluate the newest and fastest control algorithms. The system enables measurement of resonant frequency (Fr), quality factor (Q), and pull-in voltage (Vpi) within 1.5 s with repeatability better than 5 ppt (parts per thousand). A full-wafer with 420 devices under test (DUTs) has been evaluated detecting the faulty devices and providing important design specification feedback to the designers. PMID:27657087

  13. Study on chemical mechanical polishing of silicon wafer with megasonic vibration assisted.

    Science.gov (United States)

    Zhai, Ke; He, Qing; Li, Liang; Ren, Yi

    2017-09-01

    Chemical mechanical polishing (CMP) is the primary method to realize the global planarization of silicon wafer. In order to improve this process, a novel method which combined megasonic vibration to assist chemical mechanical polishing (MA-CMP) is developed in this paper. A matching layer structure of polishing head was calculated and designed. Silicon wafers are polished by megasonic assisted chemical mechanical polishing and traditional chemical mechanical polishing respectively, both coarse polishing and precision polishing experiments were carried out. With the use of megasonic vibration, the surface roughness values Ra reduced from 22.260nm to 17.835nm in coarse polishing, and the material removal rate increased by approximately 15-25% for megasonic assisted chemical mechanical polishing relative to traditional chemical mechanical polishing. Average Surface roughness values Ra reduced from 0.509nm to 0.387nm in precision polishing. The results show that megasonic assisted chemical mechanical polishing is a feasible method to improve polishing efficiency and surface quality. The material removal and finishing mechanisms of megasonic vibration assisted polishing are investigated too. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Sliding-mode control combined with improved adaptive feedforward for wafer scanner

    Science.gov (United States)

    Li, Xiaojie; Wang, Yiguang

    2018-03-01

    In this paper, a sliding-mode control method combined with improved adaptive feedforward is proposed for wafer scanner to improve the tracking performance of the closed-loop system. Particularly, In addition to the inverse model, the nonlinear force ripple effect which may degrade the tracking accuracy of permanent magnet linear motor (PMLM) is considered in the proposed method. The dominant position periodicity of force ripple is determined by using the Fast Fourier Transform (FFT) analysis for experimental data and the improved feedforward control is achieved by the online recursive least-squares (RLS) estimation of the inverse model and the force ripple. The improved adaptive feedforward is given in a general form of nth-order model with force ripple effect. This proposed method is motivated by the motion controller design of the long-stroke PMLM and short-stroke voice coil motor for wafer scanner. The stability of the closed-loop control system and the convergence of the motion tracking are guaranteed by the proposed sliding-mode feedback and adaptive feedforward methods theoretically. Comparative experiments on a precision linear motion platform can verify the correctness and effectiveness of the proposed method. The experimental results show that comparing to traditional method the proposed one has better performance of rapidity and robustness, especially for high speed motion trajectory. And, the improvements on both tracking accuracy and settling time can be achieved.

  15. Ultra-high-throughput Production of III-V/Si Wafer for Electronic and Photonic Applications

    Science.gov (United States)

    Geum, Dae-Myeong; Park, Min-Su; Lim, Ju Young; Yang, Hyun-Duk; Song, Jin Dong; Kim, Chang Zoo; Yoon, Euijoon; Kim, Sanghyeon; Choi, Won Jun

    2016-02-01

    Si-based integrated circuits have been intensively developed over the past several decades through ultimate device scaling. However, the Si technology has reached the physical limitations of the scaling. These limitations have fuelled the search for alternative active materials (for transistors) and the introduction of optical interconnects (called “Si photonics”). A series of attempts to circumvent the Si technology limits are based on the use of III-V compound semiconductor due to their superior benefits, such as high electron mobility and direct bandgap. To use their physical properties on a Si platform, the formation of high-quality III-V films on the Si (III-V/Si) is the basic technology ; however, implementing this technology using a high-throughput process is not easy. Here, we report new concepts for an ultra-high-throughput heterogeneous integration of high-quality III-V films on the Si using the wafer bonding and epitaxial lift off (ELO) technique. We describe the ultra-fast ELO and also the re-use of the III-V donor wafer after III-V/Si formation. These approaches provide an ultra-high-throughput fabrication of III-V/Si substrates with a high-quality film, which leads to a dramatic cost reduction. As proof-of-concept devices, this paper demonstrates GaAs-based high electron mobility transistors (HEMTs), solar cells, and hetero-junction phototransistors on Si substrates.

  16. CMOS-MEMS Test-Key for Extracting Wafer-Level Mechanical Properties

    Directory of Open Access Journals (Sweden)

    Pei-Zen Chang

    2012-12-01

    Full Text Available This paper develops the technologies of mechanical characterization of CMOS-MEMS devices, and presents a robust algorithm for extracting mechanical properties, such as Young’s modulus, and mean stress, through the external electrical circuit behavior of the micro test-key. An approximate analytical solution for the pull-in voltage of bridge-type test-key subjected to electrostatic load and initial stress is derived based on Euler’s beam model and the minimum energy method. Then one can use the aforesaid closed form solution of the pull-in voltage to extract the Young’s modulus and mean stress of the test structures. The test cases include the test-key fabricated by a TSMC 0.18 μm standard CMOS process, and the experimental results refer to Osterberg’s work on the pull-in voltage of single crystal silicone microbridges. The extracted material properties calculated by the present algorithm are valid. Besides, this paper also analyzes the robustness of this algorithm regarding the dimension effects of test-keys. This mechanical properties extracting method is expected to be applicable to the wafer-level testing in micro-device manufacture and compatible with the wafer-level testing in IC industry since the test process is non-destructive.

  17. Advanced single-wafer sequential multiprocessing techniques for semiconductor device fabrication

    International Nuclear Information System (INIS)

    Moslehi, M.M.; Davis, C.

    1989-01-01

    Single-wafer integrated in-situ multiprocessing (SWIM) is recognized as the future trend for advanced microelectronics production in flexible fast turn- around computer-integrated semiconductor manufacturing environments. The SWIM equipment technology and processing methodology offer enhanced equipment utilization, improved process reproducibility and yield, and reduced chip manufacturing cost. They also provide significant capabilities for fabrication of new and improved device structures. This paper describes the SWIM techniques and presents a novel single-wafer advanced vacuum multiprocessing technology developed based on the use of multiple process energy/activation sources (lamp heating and remote microwave plasma) for multilayer epitaxial and polycrystalline semiconductor as well as dielectric film processing. Based on this technology, multilayer in-situ-doped homoepitaxial silicon and heteroepitaxial strained layer Si/Ge x Si 1 - x /Si structures have been grown and characterized. The process control and the ultimate interfacial abruptness of the layer-to-layer transition widths in the device structures prepared by this technology will challenge the MBE techniques in multilayer epitaxial growth applications

  18. ASIC Wafer Test System for the ATLAS Semiconductor Tracker Front-End Chip

    International Nuclear Information System (INIS)

    Anghinolfi, F.; Bialas, W.; Busek, N.; Ciocio, A.; Cosgrove, D.; Fadeyev, V.; Flacco, C.; Gilchriese, M.; Grillo, A.A.; Haber, C.; Kaplon, J.; Lacasta, C.; Murray, W.; Niggli, H.; Pritchard, T.; Rosenbaum, F.; Spieler, H.; Stezelberger, T.; Vu, C.; Wilder, M.; Yaver, H.; Zetti, F.

    2002-01-01

    An ASIC wafer test system has been developed to provide comprehensive production screening of the ATLAS Semiconductor Tracker front-end chip (ABCD3T). The ABCD3T[1] features a 128-channel analog front-end, a digital pipeline, and communication circuitry, clocked at 40 MHz, which is the bunch crossing frequency at the LHC (Large Hadron Collider). The tester measures values and tolerance ranges of all critical IC parameters, including DC parameters, electronic noise, time resolution, clock levels and clock timing. The tester is controlled by an FPGA (ORCA3T) programmed to issue the input commands to the IC and to interpret the output data. This allows the high-speed wafer-level IC testing necessary to meet the production schedule. To characterize signal amplitudes and phase margins, the tester utilizes pin-driver, delay, and DAC chips, which control the amplitudes and delays of signals sent to the IC under test. Output signals from the IC under test go through window comparator chips to measure their levels. A probe card has been designed specifically to reduce pick-up noise that can affect the measurements. The system can operate at frequencies up to 100 MHz to study the speed limits of the digital circuitry before and after radiation damage. Testing requirements and design solutions are presented

  19. Wafer level fabrication of single cell dispenser chips with integrated electrodes for particle detection

    International Nuclear Information System (INIS)

    Schoendube, Jonas; Yusof, Azmi; Kalkandjiev, Kiril; Zengerle, Roland; Koltay, Peter

    2015-01-01

    This work presents the microfabrication and experimental evaluation of a dispenser chip, designed for isolation and printing of single cells by combining impedance sensing and drop-on-demand dispensing. The dispenser chip features 50  ×  55 µm (width × height) microchannels, a droplet generator and microelectrodes for impedance measurements. The chip is fabricated by sandwiching a dry film photopolymer (TMMF) between a silicon and a Pyrex wafer. TMMF has been used to define microfluidic channels, to serve as low temperature (75 °C) bonding adhesive and as etch mask during 300 µm deep HF etching of the Pyrex wafer. Due to the novel fabrication technology involving the dry film resist, it became possible to fabricate facing electrodes at the top and bottom of the channel and to apply electrical impedance sensing for particle detection with improved performance. The presented microchip is capable of dispensing liquid and detecting microparticles via impedance measurement. Single polystyrene particles of 10 µm size could be detected with a mean signal amplitude of 0.39  ±  0.13 V (n=439) at particle velocities of up to 9.6 mm s −1 inside the chip. (paper)

  20. Aerosol-assisted extraction of silicon nanoparticles from wafer slicing waste for lithium ion batteries.

    Science.gov (United States)

    Jang, Hee Dong; Kim, Hyekyoung; Chang, Hankwon; Kim, Jiwoong; Roh, Kee Min; Choi, Ji-Hyuk; Cho, Bong-Gyoo; Park, Eunjun; Kim, Hansu; Luo, Jiayan; Huang, Jiaxing

    2015-03-30

    A large amount of silicon debris particles are generated during the slicing of silicon ingots into thin wafers for the fabrication of integrated-circuit chips and solar cells. This results in a significant loss of valuable materials at about 40% of the mass of ingots. In addition, a hazardous silicon sludge waste is produced containing largely debris of silicon, and silicon carbide, which is a common cutting material on the slicing saw. Efforts in material recovery from the sludge and recycling have been largely directed towards converting silicon or silicon carbide into other chemicals. Here, we report an aerosol-assisted method to extract silicon nanoparticles from such sludge wastes and their use in lithium ion battery applications. Using an ultrasonic spray-drying method, silicon nanoparticles can be directly recovered from the mixture with high efficiency and high purity for making lithium ion battery anode. The work here demonstrated a relatively low cost approach to turn wafer slicing wastes into much higher value-added materials for energy applications, which also helps to increase the sustainability of semiconductor material and device manufacturing.

  1. Selection and Outcome of Portal Vein Resection in Pancreatic Cancer

    International Nuclear Information System (INIS)

    Nakao, Akimasa

    2010-01-01

    Pancreatic cancer has the worst prognosis of all gastrointestinal neoplasms. Five-year survival of pancreatic cancer after pancreatectomy is very low, and surgical resection is the only option to cure this dismal disease. The standard surgical procedure is pancreatoduodenectomy (PD) for pancreatic head cancer. The morbidity and especially the mortality of PD have been greatly reduced. Portal vein resection in pancreatic cancer surgery is one attempt to increase resectability and radicality, and the procedure has become safe to perform. Clinicohistopathological studies have shown that the most important indication for portal vein resection in patients with pancreatic cancer is the ability to obtain cancer-free surgical margins. Otherwise, portal vein resection is contraindicated

  2. Selection and Outcome of Portal Vein Resection in Pancreatic Cancer

    Energy Technology Data Exchange (ETDEWEB)

    Nakao, Akimasa [Department of Surgery II, Nagoya University Graduate School of Medicine, 65 Tsurumai-cho, Showa-ku, Nagoya 466-8550 (Japan)

    2010-11-24

    Pancreatic cancer has the worst prognosis of all gastrointestinal neoplasms. Five-year survival of pancreatic cancer after pancreatectomy is very low, and surgical resection is the only option to cure this dismal disease. The standard surgical procedure is pancreatoduodenectomy (PD) for pancreatic head cancer. The morbidity and especially the mortality of PD have been greatly reduced. Portal vein resection in pancreatic cancer surgery is one attempt to increase resectability and radicality, and the procedure has become safe to perform. Clinicohistopathological studies have shown that the most important indication for portal vein resection in patients with pancreatic cancer is the ability to obtain cancer-free surgical margins. Otherwise, portal vein resection is contraindicated.

  3. High mortality rates after non-elective colon cancer resection

    DEFF Research Database (Denmark)

    Bakker, I S; Snijders, H S; Grossmann, Irene

    2016-01-01

    AIM: Colon cancer resection in a non-elective setting is associated with high rates of morbidity and mortality. The aim of this retrospective study is to identify risk factors for overall mortality after colon cancer resection with a special focus on non-elective resection. METHOD: Data were...... obtained from the Dutch Surgical Colorectal Audit. Patients undergoing colon cancer resection in the Netherlands between January 2009 and December 2013 were included. Patient, treatment and tumour factors were analyzed in relation to the urgency of surgery. The primary outcome was the thirty day...... postoperative mortality. RESULTS: The study included 30,907 patients. In 5934 (19.2%) of patients, a non-elective colon cancer resection was performed. There was a 4.4% overall mortality rate, with significantly more deaths after non-elective surgery (8.5% vs 3.4%, P

  4. Wafer Surface Charge Reversal as a Method of Simplifying Nanosphere Lithography for Reactive Ion Etch Texturing of Solar Cells

    Directory of Open Access Journals (Sweden)

    Daniel Inns

    2007-01-01

    Full Text Available A simplified nanosphere lithography process has been developed which allows fast and low-waste maskings of Si surfaces for subsequent reactive ion etching (RIE texturing. Initially, a positive surface charge is applied to a wafer surface by dipping in a solution of aluminum nitrate. Dipping the positive-coated wafer into a solution of negatively charged silica beads (nanospheres results in the spheres becoming electrostatically attracted to the wafer surface. These nanospheres form an etch mask for RIE. After RIE texturing, the reflection of the surface is reduced as effectively as any other nanosphere lithography method, while this batch process used for masking is much faster, making it more industrially relevant.

  5. Functional Testing and Characterisation of ISFETs on Wafer Level by Means of a Micro-droplet Cell

    Directory of Open Access Journals (Sweden)

    Michael J. Schöning

    2006-04-01

    Full Text Available A wafer-level functionality testing and characterisation system for ISFETs (ion-sensitive field-effect transistor is realised by means of integration of a specifically designedcapillary electrochemical micro-droplet cell into a commercial wafer prober-station. Thedeveloped system allows the identification and selection of “good” ISFETs at the earlieststage and to avoid expensive bonding, encapsulation and packaging processes for non-functioning ISFETs and thus, to decrease costs, which are wasted for bad dies. Thedeveloped system is also feasible for wafer-level characterisation of ISFETs in terms ofsensitivity, hysteresis and response time. Additionally, the system might be also utilised forwafer-level testing of further electrochemical sensors.

  6. Endoscopic resection for gastric schwannoma with long-term outcomes.

    Science.gov (United States)

    Cai, Ming-Yan; Xu, Jia-Xin; Zhou, Ping-Hong; Xu, Mei-Dong; Chen, Shi-Yao; Hou, Jun; Zhong, Yun-Shi; Zhang, Yi-Qun; Ma, Li-Li

    2016-09-01

    Gastric schwannoma is not so recognized by clinicians as its counterparts. The efficacy of endoscopic resection has not been described yet. Our aim was to assess the efficacy and safety of endoscopic resection in the management of gastric schwannoma. Retrospective data were reviewed from January 2008 to December 2013 in our center. Fourteen patients who had endoscopic resection with the final pathology result of gastric schwannoma were included in the study. Of the 14 patients, there were 12 females and two males. The median age was 59 years (range 32-83). Thirteen tumors (92.9 %) were from the muscularis propria and one located in the submucosa. Endoscopic en bloc resection was achieved in 12 patients (12/14, 85.7 %), including seven cases of endoscopic full-thickness resection (EFTR). The mean resected tumor size was 1.73 ± 1.10 cm (range 0.3-4.0 cm). In one case, endoscopic resection was suspended due to the limited experience of EFTR during the early period of the study. In another case, due to the difficult tumor location (gastric angle) and extraluminal growth pattern, the patient was referred to laparoscopic surgery. In the 12 successful endoscopic resection cases, during the median follow-up time of 4 years (range 17-77 months, one patient lost), no tumor residue, recurrence or metastasis was found. Endoscopic resection is safe and effective in treating gastric schwannoma with excellent long-term outcomes. However, it should be performed with caution because schwannoma is mainly located in the deep muscular layer, which leads to the full-thickness resection of gastric wall.

  7. Extrahepatic bile duct resection in combination with liver resection for hilar cholangiocarcinoma : A report of 42 cases

    NARCIS (Netherlands)

    IJitsma, AJC; Appeltans, BMG; de Jong, KP; Porte, RJ; Peeters, PMJG; Slooff, MJH

    2004-01-01

    From September 1986 until December 2001, 42 patients (20 males and 22 females) underwent a combined extrahepatic bile duct resection (EHBDR) and liver resection (LR) for hilar cholangiocarcinoma (HC). The aim of this study was to analyze patient survival, morbidity, and mortality as well as to seek

  8. Stabilisation of a thin crystalline Si wafer solar cell using glass substrate; Duenne kristalline Silizium Wafer-Solarzelle mit Glastraeger stabilisiert

    Energy Technology Data Exchange (ETDEWEB)

    Muehlbauer, Maria

    2009-07-01

    An attempt was made to stabilise ultrathin crystalline silicon wafers (< 100 {mu}m) by a support material (BOROFLOAT33 by Schott Glas). It was found that the total serial resistance results mainly from the specific resistance of the back contact, and that especially the ultrathin solar cells have high recombination in the back. The ultrathin Si wafers also are slightly corrugated, which results in uneven joining of the Si wafer with the glass support. For optimisation, the solar cells of this specific types, with different thicknesses, were modelled in the one-dimensional simulation code PC1D, including all material-specific and electric properties. It was found that a slight reduction of the serial resistance will be enough for a significant improvement of the efficiency of the stabilized solar cell. With this knowledge, selective optimisation of the stabilised solar cells was possible, with the following results: 1. The improved temperature-time profile of the RTP step will improve the solar cell parameters for all Si thicknesses, which is assumed to be the result of better quality of the Al/Si back contact. 2. Thicker aluminium layers improved passivation on the back of solar cells with a thickness of 300 {mu}m and 120 {mu}m. In thinner stabilised solar cells, this measure resulted in enhanced formation of shunts and did not reduce the recombination rate on the back of the solar cell. 3. An additional optimisation step was the introduction of the so-called 'combined method' in which part of the aluminium layer is replaced by silkscreen paste. This combination, with adequate preparation, ensures uniform joining of the ultrathin silicon to the glass carrier. The resulting intermediate layers are highly homogeneous and have good fill factors and current densities for thin solar cells with a si thickness of 60 {mu}m. A decisive argument for the combined method is its near-100% reproducibility. [German] Ziel dieser Arbeit ist es sehr duenne kristalline

  9. Strategies to improve local control of resected pancreas adenocarcinoma.

    Science.gov (United States)

    Sugarbaker, Paul H

    2017-03-01

    Only approximately one in ten pancreas cancer patients is a candidate for potentially curative resection of this disease. Even this small fraction of patients has a poor prognosis following pancreatico-duodenectomy. The disease has an anatomic location that makes it difficult for the surgeon to maintain adequate margins of resection and prevent tumor spillage at the time of resection. Also, the disease is biologically aggressive and even with a complete visible resection of the disease, micrometastases are likely to remain behind. A survey of the sites for surgical treatment failure of resected pancreas cancer was performed. Also, the multiple modalities used in an attempt to improve the results of cancer resection are scrutinized. The surgical treatment failures are regional in nature and occur at the resection site and on peritoneal surfaces, within the liver, and within the regional lymph nodes. These anatomic sites account for nearly 100% of the initial sites of disease progression. Current hypothesis suggests that micrometastases released from the cancer specimen by the trauma of surgery account for the high incidence of resection site progression and peritoneal metastases. Although surgical trauma may contribute to micrometastases within the liver and lymph nodes, these are most likely present though not detected by preoperative radiologic studies. Adjuvant treatments such as neoadjuvant chemotherapy or combination systemic chemotherapy have not been associated with improved survival. Extended resections such as total pancreatectomy or extended lymphadenectomy have not been associated with benefit. However, resection with a negative margin of excision along with the removal of at least 12 lymph nodes in and around the pancreaticoduodenectomy specimen is associated with superior outcomes. A regional chemotherapy treatment that consists of hyperthermic intraperitoneal chemotherapy (HIPEC) with gemcitabine and long-term normothermic intraperitoneal chemotherapy

  10. Progress of liver resection for hepatocellular carcinoma in Taiwan.

    Science.gov (United States)

    Wu, Cheng-Chung

    2017-05-01

    Taiwan is a well-known endemic area of hepatitis B. Hepatocellular carcinoma (HCC) has consistently been the first or second highest cause of cancer death over the past 20 years. This review article describes the progress of liver resection for HCC in Taiwan in the past half century. The mortality rate for HCC resection was 15-30% in Taiwan in the 1970s. The rate decreased to 8-12% in the early 1990s, and it declined to Taiwan. Advances in non-operative modalities for HCC treatment have also helped to improve long-term outcomes of HCC resection. Technical innovations have allowed the application of complex procedures such as mesohepatectomy, unroofing hepatectomy, major portal vein thrombectomy, hepatic vein reconstruction in resection of the cranial part with preservation of the caudal part of the liver, and inferior vena cava and right atrium tumor thrombectomy under cardiopulmonary bypass. In selected patients, including patients with end-stage renal failure, renal graft recipients, patients with portal hypertension, hypersplenic thrombocytopenia and/or associated gastroesophageal varices, octogenarian, ruptured HCC, recurrent HCC and metastatic HCC can also be resected with satisfactory survival benefits. We conclude that the results of liver resection for HCC in Taiwan are improving. The indications for HCC resection continue extending with lower the surgical risks and increasing the long-term survival rate. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e-mail: journals.permissions@oup.com.

  11. 3-Tesla functional magnetic resonance imaging-guided tumor resection

    International Nuclear Information System (INIS)

    Hall, W.A.; Truwit, C.L.; Univ. of Minnesota Medical School, Minneapolis, MN; Univ. of Minnesota Medical School, Minneapolis, MN; Hennepin Country Medical Center, Minneapolis, MN

    2006-01-01

    Objective: We sought to determine the safety and efficacy of using 3-tesla (T) functional magnetic resonance imaging (fMRI) to guide brain tumor resection. Material and methods: From February 2004 to March 2006, fMRI was performed on 13 patients before surgical resection. Functional imaging was used to identify eloquent cortices for motor (8), speech (3), and motor and speech (2) activation using two different 3-T magnetic resonance (MR) scanners. Surgical resection was accomplished using a 1.5-T intraoperative MR system. Appropriate MR scan sequences were performed intraoperatively to determine and maximize the extent of the surgical resection. Results: Tumors included six oligodendrogliomas, three meningiomas, two astrocytomas and two glioblastomas multiforme. The fMRI data was accurate in all cases. After surgery, two patients had hemiparesis, two had worsening of their speech, and one had worsening of speech and motor function. Neurological function returned to normal in all patients within 1 month. Complete resections were possible in 10 patients (77%). Two patients had incomplete resections because of the proximity of their tumors to functional areas. Biopsy was performed in another patient with an astrocytoma in the motor strip. Conclusion: 3-T fMRI was accurate for locating neurologic function before tumor resection near eloquent cortex. (orig.)

  12. Synchrotron Radiation Total Reflection X-ray Fluorescence Spectroscopy for Microcontamination Analysis on Silicon Wafer Surfaces

    Energy Technology Data Exchange (ETDEWEB)

    Takaura, Norikatsu

    1997-10-01

    As dimensions in state-of-the-art CMOS devices shrink to less than 0.1 pm, even low levels of impurities on wafer surfaces can cause device degradation. Conventionally, metal contamination on wafer surfaces is measured using Total Reflection X-Ray Fluorescence Spectroscopy (TXRF). However, commercially available TXRF systems do not have the necessary sensitivity for measuring the lower levels of contamination required to develop new CMOS technologies. In an attempt to improve the sensitivity of TXRF, this research investigates Synchrotron Radiation TXRF (SR TXRF). The advantages of SR TXRF over conventional TXRF are higher incident photon flux, energy tunability, and linear polarization. We made use of these advantages to develop an optimized SR TXRF system at the Stanford Synchrotron Radiation Laboratory (SSRL). The results of measurements show that the Minimum Detection Limits (MDLs) of SR TXRF for 3-d transition metals are typically at a level-of 3x10{sup 8} atoms/cm{sup 2}, which is better than conventional TXRF by about a factor of 20. However, to use our SR TXRF system for practical applications, it was necessary to modify a commercially available Si (Li) detector which generates parasitic fluorescence signals. With the modified detector, we could achieve true MDLs of 3x10{sup 8} atoms/cm{sup 2} for 3-d transition metals. In addition, the analysis of Al on Si wafers is described. Al analysis is difficult because strong Si signals overlap the Al signals. In this work, the Si signals are greatly reduced by tuning the incident beam energy below the Si K edge. The results of our measurements show that the sensitivity for Al is limited by x-ray Raman scattering. Furthermore, we show the results of theoretical modeling of SR TXRF backgrounds consisting of the bremsstrahlung generated by photoelectrons, Compton scattering, and Raman scattering. To model these backgrounds, we extended conventional theoretical models by taking into account several aspects particular

  13. Clinical observation of local resection or enucleation for uveal melanoma.

    Science.gov (United States)

    Hong, Mei; Wei, Wenbin; Hua, Lin; Xu, Xiaoling; Shao, Lei

    2014-01-01

    Local resection is an effective method for treating the uveal melanoma. The aim of this study is to evaluate the survival and clinical outcomes of patients with uveal melanoma treated by local resection or enucleation. Totally, 167 consecutive patients with uveal melanoma were recruited for the study, of whom 57 patients were treated with local resection and 110 patients were treated with enucleation. The main outcome was measured by the visual acuity, local recurrence, eye retention, metastases, and melanoma-related mortality. There were statistically significant differences in the largest basal diameter of the tumor (t = -3.441), the tumor thickness (t = -4.140), the ciliary body infiltration (χ(2) = 8.391), and the duration of follow-up (Z = 3.995) between the two groups (P 0.05); the 5-year melanoma-related mortality was 16.27% for the group with local resection and 25.33% for enucleation (χ(2) = 1.304, P > 0.05). The 5-year local tumor recurrence rate was 29.50% and the 5-year accumulated eye retention rate was 69.00% after local resection. The visual acuity which light perception or better of 60 months after local resection was observed in 25 (92.60%) among persons retaining eye. The survival outcomes of the patients with local resection were not worse than that of the patients with enucleation, and local resection could make the patient retain eye and partial visual functions. Hence, local resection may be an effective method for patients with uveal melanoma eligible for operation.

  14. Computer Navigation-aided Resection of Sacral Chordomas

    Directory of Open Access Journals (Sweden)

    Yong-Kun Yang

    2016-01-01

    Full Text Available Background: Resection of sacral chordomas is challenging. The anatomy is complex, and there are often no bony landmarks to guide the resection. Achieving adequate surgical margins is, therefore, difficult, and the recurrence rate is high. Use of computer navigation may allow optimal preoperative planning and improve precision in tumor resection. The purpose of this study was to evaluate the safety and feasibility of computer navigation-aided resection of sacral chordomas. Methods: Between 2007 and 2013, a total of 26 patients with sacral chordoma underwent computer navigation-aided surgery were included and followed for a minimum of 18 months. There were 21 primary cases and 5 recurrent cases, with a mean age of 55.8 years old (range: 35-84 years old. Tumors were located above the level of the S3 neural foramen in 23 patients and below the level of the S3 neural foramen in 3 patients. Three-dimensional images were reconstructed with a computed tomography-based navigation system combined with the magnetic resonance images using the navigation software. Tumors were resected via a posterior approach assisted by the computer navigation. Mean follow-up was 38.6 months (range: 18-84 months. Results: Mean operative time was 307 min. Mean intraoperative blood loss was 3065 ml. For computer navigation, the mean registration deviation during surgery was 1.7 mm. There were 18 wide resections, 4 marginal resections, and 4 intralesional resections. All patients were alive at the final follow-up, with 2 (7.7% exhibiting tumor recurrence. The other 24 patients were tumor-free. The mean Musculoskeletal Tumor Society Score was 27.3 (range: 19-30. Conclusions: Computer-assisted navigation can be safely applied to the resection of the sacral chordomas, allowing execution of preoperative plans, and achieving good oncological outcomes. Nevertheless, this needs to be accomplished by surgeons with adequate experience and skill.

  15. Analysis Of Factors Affecting Gravity-Induced Deflection For Large And Thin Wafers In Flatness Measurement Using Three-Point-Support Method

    Directory of Open Access Journals (Sweden)

    Liu Haijun

    2015-12-01

    Full Text Available Accurate flatness measurement of silicon wafers is affected greatly by the gravity-induced deflection (GID of the wafers, especially for large and thin wafers. The three-point-support method is a preferred method for the measurement, in which the GID uniquely determined by the positions of the supports could be calculated and subtracted. The accurate calculation of GID is affected by the initial stress of the wafer and the positioning errors of the supports. In this paper, a finite element model (FEM including the effect of initial stress was developed to calculate GID. The influence of the initial stress of the wafer on GID calculation was investigated and verified by experiment. A systematic study of the effects of positioning errors of the support ball and the wafer on GID calculation was conducted. The results showed that the effect of the initial stress could not be neglected for ground wafers. The wafer positioning error and the circumferential error of the support were the most influential factors while the effect of the vertical positioning error was negligible in GID calculation.

  16. Thermal modelling of the multi-stage heating system with variable boundary conditions in the wafer based precision glass moulding process

    DEFF Research Database (Denmark)

    Sarhadi, Ali; Hattel, Jesper Henri; Hansen, Hans Nørgaard

    2012-01-01

    pressures. Finally, the three-dimensional modelling of the multi-stage heating system in the wafer based glass moulding process is simulated with the FEM software ABAQUS for a particular industrial application for mobile phone camera lenses to obtain the temperature distribution in the glass wafer...

  17. Surgery of resectable nonfunctioning neuroendocrine pancreatic tumors.

    Science.gov (United States)

    Dralle, Henning; Krohn, Sabine L; Karges, Wolfram; Boehm, Bernhard O; Brauckhoff, Michael; Gimm, Oliver

    2004-12-01

    Nonfunctioning neuroendocrine pancreatic tumors (NFNEPTs) comprise about one-third of pancreatic endocrine tumors. Based on immunohistochemistry, nonfunctioning tumors are difficult to distinguish from functioning ones; therefore the final diagnosis is basically the result of a synopsis of pathology and clinical data. Owing to their incapacity to produce hormone-dependent symptoms, NFNEPTs are detected incidentally or because of uncharacteristic symptoms resulting from local or distant growth. About two-thirds of NFNEPTs are located in the pancreatic head, so jaundice may be a late symptom of this tumor. Modern diagnostic procedures are best applied by a stepwise approach: first endoscopic ultrasonography and computed tomography/magnetic resonance imaging followed by somatostatin receptor scintigraphy or positron emission tomography (or both). Due to significant false-positive and false-negative findings, for decision-making the latter should be confirmed by a second imaging modality. Regarding indications for surgery and the surgical approach to the pancreas, three pancreatic manifestations of NFNEPTs can be distinguished: (1) solitary benign non-multiple endocrine neoplasia type 1 (non-MEN-1); (2) multiple benign MEN-1; and (3) malignant NFNEPTs. Reviewing the literature and including our experience with 18 NFNEPTs (8 benign, 10 malignant) reported here, the following conclusions can be drawn: (1) Solitary benign non-MEN-1 NFNEPTs can be removed by enucleation or by pancreas-, spleen-, and duodenum-preserving techniques in most cases. The choice of surgical technique depends on the location and site of the tumor and its anatomic relation to the pancreatic duct. (2) With multiple benign MEN-1 NFNEPTs, because of the characteristics of the underlying disease a preferred, more conservative concept (removal of only macrolesions) competes with a more radical procedure (left pancreatic resection with enucleation of head macrolesions). Further studies are necessary to

  18. Laparoscopic Resection of Cesarean Scar Ectopic Pregnancy.

    Science.gov (United States)

    Ades, Alex; Parghi, Sneha

    To demonstrate a technique for the laparoscopic surgical management of cesarean section scar ectopic pregnancy. Step-by-step presentation of the procedure using video (Canadian Task Force classification III). Cesarean section scar ectopic pregnancy is a rare form of ectopic pregnancy with an incidence ranging from 1:1800 to 1:2216. Over the last decade, the incidence seems to be on the rise with increasing rates of cesarean deliveries and early use of Doppler ultrasound. These pregnancies can lead to life-threatening hemorrhage, uterine rupture, and hysterectomy if not managed promptly. Local or systemic methotrexate therapy has been used successfully but can result in prolonged hospitalization, requires long-term follow-up, and in some cases treatment can fail. In the hands of a trained operator, laparoscopic resection can be performed to manage this type of pregnancy. Consent was obtained from the patient, and exemption was granted from the local Internal Review Board (The Womens' Hospital, Parkville). In this video we describe our technique for laparoscopic management of a cesarean scar ectopic pregnancy. We present the case of a 34-year-old G4P2T1 with the finding of a live 8-week pregnancy embedded in the cesarean section scar. The patient had undergone 2 previous uncomplicated cesarean sections at term. On presentation her β-human chorionic gonadotropin (β-hCG) level was 52 405 IU/L. She was initially managed with an intragestational sac injection of potassium chloride and methotrexate, followed by 4 doses of intramuscular methotrexate. Despite these conservative measures, the level of β-hCG did not adequately fall and an ultrasound showed a persistent 4-cm mass. A decision was made to proceed with surgical treatment in the form of a laparoscopic resection of the ectopic pregnancy. The surgery was uneventful, and the patient was discharged home within 24 hours of her procedure. Her serial β-hCG levels were followed until complete resolution

  19. Resection of pancreatic cancer in Europe and USA

    DEFF Research Database (Denmark)

    Huang, Lei; Jansen, Lina; Balavarca, Yesilda

    2018-01-01

    assessed using multivariable logistic regression models. RESULTS: A total of 153 698 records were analysed. In population-based registries in 2012-2014, resection rates ranged from 13.2% (Estonia) to 21.2% (Slovenia) overall and from 34.8% (Norway) to 68.7% (Denmark) for stage I-II tumours, with great...... performance status, tumour location and size were also associated with resection application. CONCLUSION: Rates of PaC resection remain low in Europe and USA with great international variations. Further studies are warranted to explore reasons for these variations....

  20. Resection of the Tooth Apex with Diode Laser

    Directory of Open Access Journals (Sweden)

    Uzunov Tz.

    2014-06-01

    Full Text Available An “in vitro” experimental study has been carried out on 70 extracted teeth. A laser resection of the root apex has been carried out with diode laser beam with a wavelength of - 810 ± 10 nm. Sequentially a radiation with increasing power has been applied, as follows: 1,3 W, 2W, 3W, 4W, 5W, 6W, 7W, in electro surgery mode. Successful resection of the tooth apex has been performed at: 3W; 4W; 5W; 6W and 7W power. It was established that when laser resected the tooth apex carbonizes.

  1. Rapid rehabilitation in elderly patients after laparoscopic colonic resection

    DEFF Research Database (Denmark)

    Bardram, Linda; Funch-Jensen, P; Kehlet, H

    2000-01-01

    invasive procedure. In the present study the laparoscopic approach was combined with a perioperative multimodal rehabilitation protocol. METHODS: After laparoscopically assisted colonic resection, patients were treated with epidural local anaesthesia for 2 days, early mobilization and enteral nutrition...... rehabilitation protocol of pain relief, early mobilization and oral nutrition........ Routine use of morphine and traditional tubes, drains and prolonged bladder catheterization was avoided. RESULTS: Laparoscopic resection was intended in 50 consecutive patients, of median age 81 years. The conversion rate to open resection was 22 per cent. In patients in whom the procedure was completed...

  2. DNA resection in eukaryotes: deciding how to fix the break.

    Science.gov (United States)

    Huertas, Pablo

    2010-01-01

    DNA double-strand breaks are repaired by different mechanisms, including homologous recombination and nonhomologous end-joining. DNA-end resection, the first step in recombination, is a key step that contributes to the choice of DSB repair. Resection, an evolutionarily conserved process that generates single-stranded DNA, is linked to checkpoint activation and is critical for survival. Failure to regulate and execute this process results in defective recombination and can contribute to human disease. Here I review recent findings on the mechanisms of resection in eukaryotes, from yeast to vertebrates, provide insights into the regulatory strategies that control it, and highlight the consequences of both its impairment and its deregulation.

  3. New overlay measurement technique with an i-line stepper using embedded standard field image alignment marks for wafer bonding applications

    Science.gov (United States)

    Kulse, P.; Sasai, K.; Schulz, K.; Wietstruck, M.

    2017-06-01

    In the last decades the semiconductor technology has been driven by Moore's law leading to high performance CMOS technologies with feature sizes of less than 10 nm [1]. It has been pointed out that not only scaling but also the integration of novel components and technology modules into CMOS/BiCMOS technologies is becoming more attractive to realize smart and miniaturized systems [2]. Driven by new applications in the area of communication, health and automation, new components and technology modules such as BiCMOS embedded RF-MEMS, high-Q passives, Sibased microfluidics and InP-SiGe BiCMOS heterointegration have been demonstrated [3-6]. In contrast to standard VLSI processes fabricated on front side of the silicon wafer, these new technology modules require addition backside processing of the wafer; thus an accurate alignment between the front and backside of the wafer is mandatory. In previous work an advanced back to front side alignment technique and implementation into IHP's 0.25/0.13 μm high performance SiGe:C BiCMOS backside process module has been presented [7]. The developed technique enables a high resolution and accurate lithography on the backside of BiCMOS wafer for additional backside processing. In addition to the aforementioned back side process technologies, new applications like Through-Silicon Vias (TSV) for interposers and advanced substrate technologies for 3D heterogeneous integration demand not only single wafer fabrication but also processing of wafer stacks provided by temporary and permanent wafer bonding [8]. Therefore, the available overlay measurement techniques are not suitable if overlay and alignment marks are realized at the bonding interface of a wafer stack which consists of both a silicon device and a silicon carrier wafer. The former used EVG 40NT automated overlay measurement system, which use two opposite positioned microscopes inspecting simultaneous the wafer back and front side, is not capable measuring embedded overlay

  4. Formation of cross-cutting structures with different porosity on thick silicon wafers

    Directory of Open Access Journals (Sweden)

    Vera A. Yuzova

    2017-06-01

    The second type pass-through structures include a macroporous silicon layer with a thickness of 250 μm which interlock in the depth of the silicon wafer to form a cavity with a size of 4–8 μm. For the formation of the second type structures we only used the first one of the abovementioned stages, the etching time being longer, i.e. 210 min. All the etching procedures were carried out in a cooling chamber at 5 °C. The developed technology will provided for easier and more reliable formation of the monolithic structures of membrane-electrode assembly micro fuel cells.

  5. A Lateral Differential Resonant Pressure Microsensor Based on SOI-Glass Wafer-Level Vacuum Packaging

    Science.gov (United States)

    Xie, Bo; Xing, Yonghao; Wang, Yanshuang; Chen, Jian; Chen, Deyong; Wang, Junbo

    2015-01-01

    This paper presents the fabrication and characterization of a resonant pressure microsensor based on SOI-glass wafer-level vacuum packaging. The SOI-based pressure microsensor consists of a pressure-sensitive diaphragm at the handle layer and two lateral resonators (electrostatic excitation and capacitive detection) on the device layer as a differential setup. The resonators were vacuum packaged with a glass cap using anodic bonding and the wire interconnection was realized using a mask-free electrochemical etching approach by selectively patterning an Au film on highly topographic surfaces. The fabricated resonant pressure microsensor with dual resonators was characterized in a systematic manner, producing a quality factor higher than 10,000 (~6 months), a sensitivity of about 166 Hz/kPa and a reduced nonlinear error of 0.033% F.S. Based on the differential output, the sensitivity was increased to two times and the temperature-caused frequency drift was decreased to 25%. PMID:26402679

  6. Output blue light evaluation for phosphor based smart white LED wafer level packages.

    Science.gov (United States)

    Kolahdouz, Zahra; Rostamian, Ali; Kolahdouz, Mohammadreza; Ma, Teng; van Zeijl, Henk; Zhang, Kouchi

    2016-02-22

    This study presents a blue light detector for evaluating the output light of phosphor based white LED package. It is composed of a silicon stripe-shaped photodiode designed and implemented in a 2 μm BiCMOS process which can be used for wafer level integration of different passive and active devices all in just 5 lithography steps. The final device shows a high selectivity to blue light. The maximum responsivity at 480 nm is matched with the target blue LED illumination. The designed structure have better responsivity compared to simple photodiode structure due to reducing the effect of dead layer formation close to the surface because of implantation. It has also a two-fold increase in the responsivity and quantum efficiency compared to previously similar published sensors.

  7. "Silicon millefeuille": From a silicon wafer to multiple thin crystalline films in a single step

    Science.gov (United States)

    Hernández, David; Trifonov, Trifon; Garín, Moisés; Alcubilla, Ramon

    2013-04-01

    During the last years, many techniques have been developed to obtain thin crystalline films from commercial silicon ingots. Large market applications are foreseen in the photovoltaic field, where important cost reductions are predicted, and also in advanced microelectronics technologies as three-dimensional integration, system on foil, or silicon interposers [Dross et al., Prog. Photovoltaics 20, 770-784 (2012); R. Brendel, Thin Film Crystalline Silicon Solar Cells (Wiley-VCH, Weinheim, Germany 2003); J. N. Burghartz, Ultra-Thin Chip Technology and Applications (Springer Science + Business Media, NY, USA, 2010)]. Existing methods produce "one at a time" silicon layers, once one thin film is obtained, the complete process is repeated to obtain the next layer. Here, we describe a technology that, from a single crystalline silicon wafer, produces a large number of crystalline films with controlled thickness in a single technological step.

  8. The deposition of silicon nitride films under low pressure on wafers up to 200 mm

    Directory of Open Access Journals (Sweden)

    Nalivaiko O. Yu.

    2012-12-01

    Full Text Available The influence of silicon nitride deposition condition on parameters of the obtained films has been investigated. It has been found that the deposition rate of silicon nitride films decreases with deposition temperature decreasing, and at the same time the within wafer thickness uniformity improves. It allows performing the reproducible deposition of silicon nitride films with thickness of less than 10 nm. It has been found that in order to decrease the oxidation depth of silicon nitride, it is appropriate to carry out the oxidation under 850—900°C. The developed process of silicon nitride deposition made it possible to obtain reservoir capacitors with specific capacitance of 3,8—3,9 fF/μm2 at film thickness of 7,0 nm.

  9. Large Out-of-Plane Displacement Bistable Electromagnetic Microswitch on a Single Wafer.

    Science.gov (United States)

    Miao, Xiaodan; Dai, Xuhan; Huang, Yi; Ding, Guifu; Zhao, Xiaolin

    2016-05-05

    This paper presents a bistable microswitch fully batch-fabricated on a single glass wafer, comprising of a microactuator, a signal transformer, a microspring and a permanent magnet. The bistable mechanism of the microswitch with large displacement of 160 μm depends on the balance of the magnetic force and elastic force. Both the magnetic force and elastic force were optimized by finite-element simulation to predict the reliable of the device. The prototype was fabricated and characterized. By utilizing thick laminated photoresist sacrificial layer, the large displacement was obtained to ensure the insulation of the microswitch. The testing results show that the microswitch realized the bistable mechanism at a 3-5 V input voltage and closed in 0.96 ms, which verified the simulation.

  10. Characterizations of ball impact responses of wafer-level chip-scale packages

    Energy Technology Data Exchange (ETDEWEB)

    Lai, Y.-S. [Stress-Reliability Laboratory, Advanced Semiconductor Engineering Inc., 26 Chin 3rd Road, Nantze Export Processing Zone, 811 Nantze, Kaohsiung, Taiwan (China)], E-mail: yishao_lai@aseglobal.com; Yeh, C.-L.; Chang, H.-C.; Kao, C.-L. [Stress-Reliability Laboratory, Advanced Semiconductor Engineering Inc., 26 Chin 3rd Road, Nantze Export Processing Zone, 811 Nantze, Kaohsiung, Taiwan (China)

    2008-02-14

    We present in this paper ball impact test results conducted on package-level 95.5Sn-4Ag-0.5Cu solder joints of a wafer-level chip-scale package, under an impact velocity of 1.4 m/s. Scanning electron microscopy was employed to investigate intermetallic morphologies and fractographs around the under bump metallurgy before and after the ball impact test, respectively. An explicit three-dimensional finite element analysis was also conducted and the comparison between computed and measured impact force profiles are presented. The comparison indicates that when material properties and strengths are apppropriately and reasonably selected, the finite element analysis is capable of capturing relevant ball impact test (BIT)-induced transient structural responses of the solder joint prior to the initiation of fracturing.

  11. Effect of dose and size on defect engineering in carbon cluster implanted silicon wafers

    Science.gov (United States)

    Okuyama, Ryosuke; Masada, Ayumi; Shigematsu, Satoshi; Kadono, Takeshi; Hirose, Ryo; Koga, Yoshihiro; Okuda, Hidehiko; Kurita, Kazunari

    2018-01-01

    Carbon-cluster-ion-implanted defects were investigated by high-resolution cross-sectional transmission electron microscopy toward achieving high-performance CMOS image sensors. We revealed that implantation damage formation in the silicon wafer bulk significantly differs between carbon-cluster and monomer ions after implantation. After epitaxial growth, small and large defects were observed in the implanted region of carbon clusters. The electron diffraction pattern of both small and large defects exhibits that from bulk crystalline silicon in the implanted region. On the one hand, we assumed that the silicon carbide structure was not formed in the implanted region, and small defects formed because of the complex of carbon and interstitial silicon. On the other hand, large defects were hypothesized to originate from the recrystallization of the amorphous layer formed by high-dose carbon-cluster implantation. These defects are considered to contribute to the powerful gettering capability required for high-performance CMOS image sensors.

  12. Micro-characterisation of Si wafers by high-pressure thermopower technique

    International Nuclear Information System (INIS)

    Ovsyannikov, Sergey V.; Shchennikov Jr, Vsevolod V.; Shaydarova, Nadezda A.; Shchennikov, Vladimir V.; Misiuk, Andrzej; Yang Deren; Antonova, Irina V.; Shamin, Sergey N.

    2006-01-01

    In the present work a set of Czochralski-grown silicon wafers (Cz-Si) differently pre-treated (annealed at high temperatures in pressure medium, doped with nitrogen, implanted with high-energy hydrogen ions) has been characterised by high-pressure thermopower S technique in the phase transitions region (0-20GPa). The shifts were observed in pressure of semiconductor-metal phase transition P t determined from the S(P) under pre-treatments. For the first time, correlation dependence has been established between high-pressure thermoelectric properties on the one hand and concentration of residual interstitial oxygen c O (which is always present in Cz-Si) on the other hand. The dependence exhibited a maximum of P t near c O ∼9x10 17 cm -3

  13. A Fuzzy-Neural Ensemble and Geometric Rule Fusion Approach for Scheduling a Wafer Fabrication Factory

    Directory of Open Access Journals (Sweden)

    Hsin-Chieh Wu

    2013-01-01

    Full Text Available In this study, the fuzzy-neural ensemble and geometric rule fusion approach is presented to optimize the performance of job dispatching in a wafer fabrication factory with an intelligent rule. The proposed methodology is a modification of a previous study by fusing two dispatching rules and diversifying the job slacks in novel ways. To this end, the geometric mean of the neighboring distances of slacks is maximized. In addition, the fuzzy c-means (FCM and backpropagation network (BPN ensemble approach was also proposed to estimate the remaining cycle time of a job, which is an important input to the new rule. A new aggregation mechanism was also designed to enhance the robustness of the FCM-BPN ensemble approach. To validate the effectiveness of the proposed methodology, some experiments have been conducted. The experimental results did support the effectiveness of the proposed methodology.

  14. Atomic force and confocal microscopy for the study of cortical cells cultured on silicon wafers.

    Science.gov (United States)

    Ma, J; Cui, F Z; Liu, B F; Xu, Q Y

    2007-05-01

    The primary cortical cells were selected as a model to study the adherence and neural network development on chemically roughened silicon substrates without any coatings using confocal laser scanning microscopy (CLSM) and atomic force microscopy (AFM). The silicon substrates have a nano-range roughness (RMS) achieved by chemical etching using hydrofluoric (HF) acid. After 7 days of culturing, the neurons were observed to connect together and form dense neural networks. Furthermore, AFM results revealed that some porous structures at a few micrometer range existed between the neuron cells and the silicon substrates. It is suggested that the porous structures are made of extracellular matrix (ECM) components and play an important role in the neuronal adhesion and neurite outgrowth on the inert silicon wafers.

  15. Flexoelectric piezoelectric metamaterials based on the bending of ferroelectric ceramic wafers

    Science.gov (United States)

    Zhang, Xiaotong; Liu, Jiliang; Chu, Mingjin; Chu, Baojin

    2016-08-01

    Conventional piezoelectric ceramics lose their piezoelectric properties near the Curie temperature (Tc), which limits their application at high temperatures. One approach to resolving this issue is to design flexoelectric piezoelectric composites or piezoelectric metamaterials by exploiting the flexoelectric effect of the ferroelectric materials. In this work, an experimental study on two designs of flexoelectric metamaterials is demonstrated. When a ferroelectric ceramic wafer is placed on a metal ring or has a domed shape, which is produced through the diffusion between two pieces of ferroelectric ceramic of different compositions at high temperatures, an apparent piezoelectric response originating from the flexoelectric effect can be measured under a stress. The apparent piezoelectric response of the materials based on the designs can be sustained well above Tc. This study provides an approach to designing materials for high-temperature electromechanical applications.

  16. Wafer scale millimeter-wave integrated circuits based on epitaxial graphene in high data rate communication

    Science.gov (United States)

    Habibpour, Omid; He, Zhongxia Simon; Strupinski, Wlodek; Rorsman, Niklas; Zirath, Herbert

    2017-02-01

    In recent years, the demand for high data rate wireless communications has increased dramatically, which requires larger bandwidth to sustain multi-user accessibility and quality of services. This can be achieved at millimeter wave frequencies. Graphene is a promising material for the development of millimeter-wave electronics because of its outstanding electron transport properties. Up to now, due to the lack of high quality material and process technology, the operating frequency of demonstrated circuits has been far below the potential of graphene. Here, we present monolithic integrated circuits based on epitaxial graphene operating at unprecedented high frequencies (80-100 GHz). The demonstrated circuits are capable of encoding/decoding of multi-gigabit-per-second information into/from the amplitude or phase of the carrier signal. The developed fabrication process is scalable to large wafer sizes.

  17. Magnetoresistance of tungsten thin wafer at the multichannel surface scattering of conduction electrons

    International Nuclear Information System (INIS)

    Lutsishin, P.P.; Nakhodkin, T.N.

    1982-01-01

    The magnetoresistance of tungsten thin wafer with the (110) surface was studied at the adsorption of tungsten dioxide. The method of low-energy electron diffraction was used to study the symmetry of ordered surface structures. Using the method of the magnetoresistance measurement the character of the scattering of conduction electrons was investigated. THe dependence of magnetoresistance on the surface concentration of tungsten dioxide correlated w1th the structure of the surface layer of atoms, what was explained with allowance for diffraction of conduction electrons at the metal boundary. The magnetoresistance maximum for the (2x2) structure, which characterised decrease in surface conduction under the conditions of static skin effect, was explained by multichannel mirror reflection with the recombinations of electron and ho.le sections of Fermi Surface

  18. Metal-induced rapid transformation of diamond into single and multilayer graphene on wafer scale.

    Science.gov (United States)

    Berman, Diana; Deshmukh, Sanket A; Narayanan, Badri; Sankaranarayanan, Subramanian K R S; Yan, Zhong; Balandin, Alexander A; Zinovev, Alexander; Rosenmann, Daniel; Sumant, Anirudha V

    2016-07-04

    The degradation of intrinsic properties of graphene during the transfer process constitutes a major challenge in graphene device fabrication, stimulating the need for direct growth of graphene on dielectric substrates. Previous attempts of metal-induced transformation of diamond and silicon carbide into graphene suffers from metal contamination and inability to scale graphene growth over large area. Here, we introduce a direct approach to transform polycrystalline diamond into high-quality graphene layers on wafer scale (4 inch in diameter) using a rapid thermal annealing process facilitated by a nickel, Ni thin film catalyst on top. We show that the process can be tuned to grow single or multilayer graphene with good electronic properties. Molecular dynamics simulations elucidate the mechanism of graphene growth on polycrystalline diamond. In addition, we demonstrate the lateral growth of free-standing graphene over micron-sized pre-fabricated holes, opening exciting opportunities for future graphene/diamond-based electronics.

  19. High sensitivity detection and characterization of the chemical state of trace element contamination on silicon wafers

    CERN Document Server

    Pianetta, Piero A; Baur, K; Brennan, S; Homma, T; Kubo, N

    2003-01-01

    Increasing the speed and complexity of semiconductor integrated circuits requires advanced processes that put extreme constraints on the level of metal contamination allowed on the surfaces of silicon wafers. Such contamination degrades the performance of the ultrathin SiO sub 2 gate dielectrics that form the heart of the individual transistors. Ultimately, reliability and yield are reduced to levels that must be improved before new processes can be put into production. It should be noted that much of this metal contamination occurs during the wet chemical etching and rinsing steps required for the manufacture of integrated circuits and industry is actively developing new processes that have already brought the metal contamination to levels beyond the measurement capabilities of conventional analytical techniques. The measurement of these extremely low contamination levels has required the use of synchrotron radiation total reflection X-ray fluorescence (SR-TXRF) where sensitivities 100 times better than conv...

  20. Geometrical Deviation and Residual Strain in Novel Silicon-on-Aluminium-Nitride Bonded Wafers

    Science.gov (United States)

    Men, Chuan-Ling; Xu, Zheng; Wu, Yan-Jun; An, Zheng-Hua; Xie, Xin-Yun; Lin, Cheng-Lu

    2002-11-01

    Aluminium nitride (AlN), with much higher thermal conductivity, is considered to be an excellent alternative to the SiO2 layer in traditional silicon-on-insulator (SOI) materials. The silicon-on-aluminium-nitride (SOAN) structure was fabricated by the smart-cut process to alleviate the self-heating effects for traditional SOI. The convergent beam Kikuchi line diffraction pattern results show that some rotational misalignment exists when two wafers are bonded, which is about 3°. The high-resolution x-ray diffraction result indicates that, before annealing at high temperature, the residual lattice strain in the top silicon layer is tensile. After annealing at 1100°C for an hour, the strain in the top Si decreases greatly and reverses from tensile to slightly compressive as a result of viscous flow of AlN.

  1. Thermomechanical Reliability Study of Benzocyclobutene Film in Wafer-Level Chip-Size Package

    Science.gov (United States)

    Lee, K.-O.

    2012-04-01

    A new wafer-level chip-scale package process for high-performance, low-cost packaging has been developed based on passivation with low dielectric constant. This process is simpler and shorter when using permanent photosensitive benzocyclobutene (BCB) compared with the conventional process. However, cracks nucleating on the BCB cause serious reliability problems. The major reasons for cracking of the BCB layer seem to be both thermal stress and a shortage of BCB cross-linking agent (cyclobutene). The stress was reduced by optimizing the thickness of the BCB layer and the underlying stress buffer layer. The BCB cracking resistance was improved by creating more cross-linking agent at the final curing process through modification of the photolithography processes.

  2. Wafer-Scale Nanopillars Derived from Block Copolymer Lithography for Surface-Enhanced Raman Spectroscopy

    DEFF Research Database (Denmark)

    Li, Tao; Wu, Kaiyu; Rindzevicius, Tomas

    2016-01-01

    We report a novel nanofabrication process via block copolymer lithography using solvent vapor annealing. The nanolithography process is facile and scalable, enabling fabrication of highly ordered periodic patterns over entire wafers as substrates for surface-enhanced Raman spectroscopy (SERS......). Direct silicon etching with high aspect ratio templated by the block copolymer mask is realized without any intermediate layer or external precursors. Uniquely, an atomic layer deposition (ALD)-assisted method is introduced to allow reversing of the morphology relative to the initial pattern. As a result......, highly ordered silicon nanopillar arrays are fabricated with controlled aspect ratios. After metallization, the resulting nanopillar arrays are suitable for SERS applications. These structures readily exhibit an average SERS enhancement factor of above 108, SERS uniformities of 8.5% relative standard...

  3. Trace element analysis on Si wafer surfaces by TXRF at the ID32 ESRF undulator beamline.

    Science.gov (United States)

    Ortega, L; Comin, F; Formoso, V; Stierle, A

    1998-05-01

    Synchrotron radiation total-reflection X-ray fluorescence (SR-TXRF) has been applied to the impurity analysis of Si wafers using a third-generation synchrotron radiation undulator source. A lower limit of detectability (LLD) for Ni atoms of 17 fg (1.7 x 10(8) atoms cm(-2)) has been achieved with an optical set-up based on an Si(111) double-crystal monochromator and a horizontal sample geometry. These first results are very promising for synchrotron radiation trace element analysis since we estimate that it is possible to lower the LLD by a factor of about 25 by employing appropriate optics and detectors. The use of a crystal monochromator opens new possibilities to perform absorption and scattering experiments (NEXAFS and X-ray standing-wave methods) for chemical and structural analysis of ultratrace elements.

  4. Sidewall patterning—a new wafer-scale method for accurate patterning of vertical silicon structures

    Science.gov (United States)

    Westerik, P. J.; Vijselaar, W. J. C.; Berenschot, J. W.; Tas, N. R.; Huskens, J.; Gardeniers, J. G. E.

    2018-01-01

    For the definition of wafer scale micro- and nanostructures, in-plane geometry is usually controlled by optical lithography. However, options for precisely patterning structures in the out-of-plane direction are much more limited. In this paper we present a versatile self-aligned technique that allows for reproducible sub-micrometer resolution local modification along vertical silicon sidewalls. Instead of optical lithography, this method makes smart use of inclined ion beam etching to selectively etch the top parts of structures, and controlled retraction of a conformal layer to define a hard mask in the vertical direction. The top, bottom or middle part of a structure could be selectively exposed, and it was shown that these exposed regions can, for example, be selectively covered with a catalyst, doped, or structured further.

  5. Circumferential resection margin (CRM) positivity after MRI assessment and adjuvant treatment in 189 patients undergoing rectal cancer resection.

    Science.gov (United States)

    Simpson, G S; Eardley, N; McNicol, F; Healey, P; Hughes, M; Rooney, P S

    2014-05-01

    The management of rectal cancer relies on accurate MRI staging. Multi-modal treatments can downstage rectal cancer prior to surgery and may have an effect on MRI accuracy. We aim to correlate the findings of MRI staging of rectal cancer with histological analysis, the effect of neoadjuvant therapy on this and the implications of circumferential resection margin (CRM) positivity following neoadjuvant therapy. An analysis of histological data and radiological staging of all cases of rectal cancer in a single centre between 2006 and 2011 were conducted. Two hundred forty-one patients had histologically proved rectal cancer during the study period. One hundred eighty-two patients underwent resection. Median age was 66.6 years, and male to female ratio was 13:5. R1 resection rate was 11.1%. MRI assessments of the circumferential resection margin in patients without neoadjuvant radiotherapy were 93.6 and 88.1% in patients who underwent neoadjuvant radiotherapy. Eighteen patients had predicted positive margins following chemoradiotherapy, of which 38.9% had an involved CRM on histological analysis. MRI assessment of the circumferential resection margin in rectal cancer is associated with high accuracy. Neoadjuvant chemoradiotherapy has a detrimental effect on this accuracy, although accuracy remains high. In the presence of persistently predicted positive margins, complete resection remains achievable but may necessitate a more radical approach to resection.

  6. Long Term Changes in Muscles around the Knee Joint after ACL Resection in Rats: Comparisons of ACL-Resected, Contralateral and Normal Limb

    Directory of Open Access Journals (Sweden)

    Mahiro Ohno, Hiroto Fujiya, Katsumasa Goto, Mitsutoshi Kurosaka, Yuji Ogura, Kanaka Yatabe, Takaaki Kudo, Hajime Kobayashi, Hisateru Niki, Haruki Musha

    2017-09-01

    Full Text Available The purpose of this study was to investigate the long-term effects of anterior cruciate ligament (ACL resection on the morphological and contractile characteristics of rectus femoris (RF and semimembranosus (SM muscles in both injured and contralateral hindlimbs in rats. Wistar male rats (8-week old were used. Rats were divided into two groups; ACL-resected and (sham-operated control groups. Furthermore, right and left limbs of rats in the ACL-resected group were assigned as ACL-resected and contralateral groups, respectively, at 1 day, 1, 4, and 48 weeks after ACL resection. No ACL-resection-associated changes in the mass of both muscles were observed 1 week after ACL resection. On the other hand, ACL-resection-associated reduction on mean fiber cross-sectional area (fiber CSA in RF muscle lasted 48 weeks after ACL resection. Furthermore, ACL-resection associated increase in fiber composition of type I fiber in RF muscle in contralateral limbs. In addition, long-term effects of ACL resection were observed in both ACL-resected and contralateral limbs. Evidences from this study suggested that ACL resection may cause to change in the morphological (fiber CSA and contractile (distribution of fiber types properties of skeletal muscles around the knee joint in not only injured but also contralateral limb. Rehabilitation for quantitative and qualitative muscle changes by ACL resection may be required a special care for a long-term period.

  7. Electrochemical isotropic texturing of mc-Si wafers in KOH solution

    International Nuclear Information System (INIS)

    Abburi, M.; Boström, T.; Olefjord, I.

    2013-01-01

    Boron doped multicrystalline Si-wafers were anodically polarized in 2 M KOH and 4 M KOH at 40 °C and 50 °C. The applied potentials were 25 V, 30 V, 40 V and 50 V. The morphology of the textured surfaces, the surface products and the light reflectivity were analyzed by utilizing SEM, XPS and Lambda UV/Vis/NIR spectrophotometer, respectively. Isotropic texturing was obtained. The lowest average reflectivity, 17%, was achieved after pre-etching for 10 min and polarization at 40 V for 10 min in 4 M KOH at 50 °C. That reflection value is half of that measured on a chemical pre-etched surface, 34%. By increasing the voltage to 50 V the reflectivity rises to 28%. Polarizations to 25 V and 30 V at 50 °C in both solutions give local pores in the μm-range. The etch attack initiation is located at protrusions on the surface. At 40 V and 50 V in both solutions the pores are extended onto the entire surface. The width of the pores is about 10 μm. Inside the micro-pores, nm-pores are formed; their lateral size is in the range 100 nm–200 nm. A mechanism for the anodic dissolution reactions is discussed. - Highlights: ► A method to form isotropic textures on mc-Si wafers in KOH solution is presented. ► The method is based on anodic polarization of silicon in KOH at high potentials. ► Evolution of surface morphology is studied by varying the etch parameters. ► Isotropic textures with lowest average reflectivity are obtained at 40 V. ► A reaction model for texturing mechanism is discussed in the light of XPS data

  8. Consequences of atomic layer etching on wafer scale uniformity in inductively coupled plasmas

    Science.gov (United States)

    Huard, Chad M.; Lanham, Steven J.; Kushner, Mark J.

    2018-04-01

    Atomic layer etching (ALE) typically divides the etching process into two self-limited reactions. One reaction passivates a single layer of material while the second preferentially removes the passivated layer. As such, under ideal conditions the wafer scale uniformity of ALE should be independent of the uniformity of the reactant fluxes onto the wafers, provided all surface reactions are saturated. The passivation and etch steps should individually asymptotically saturate after a characteristic fluence of reactants has been delivered to each site. In this paper, results from a computational investigation are discussed regarding the uniformity of ALE of Si in Cl2 containing inductively coupled plasmas when the reactant fluxes are both non-uniform and non-ideal. In the parameter space investigated for inductively coupled plasmas, the local etch rate for continuous processing was proportional to the ion flux. When operated with saturated conditions (that is, both ALE steps are allowed to self-terminate), the ALE process is less sensitive to non-uniformities in the incoming ion flux than continuous etching. Operating ALE in a sub-saturation regime resulted in less uniform etching. It was also found that ALE processing with saturated steps requires a larger total ion fluence than continuous etching to achieve the same etch depth. This condition may result in increased resist erosion and/or damage to stopping layers using ALE. While these results demonstrate that ALE provides increased etch depth uniformity, they do not show an improved critical dimension uniformity in all cases. These possible limitations to ALE processing, as well as increased processing time, will be part of the process optimization that includes the benefits of atomic resolution and improved uniformity.

  9. Wafer-edge defect reduction for tri-layer materials in BEOL applications

    Science.gov (United States)

    Du, J. R.; Huang, C. H.; Yang, Elvis; Yang, T. H.; Chen, K. C.; Lu, Chih-Yuan

    2011-03-01

    As the semiconductor feature size continues to shrink, the thickness of photo resist needs to be thinner and thinner to prevent resist features from collapse. Coupling with the need of high NA lithography for small feature patterning, both the reflectance control and the etch budget on resist thickness are becoming major challenges for lithographers. One way to simultaneously satisfy the needs of superior low reflectance, sufficient etch resistance and minimizing the resist feature collapse is adopting tri-layer lithography scheme. The tri-layer scheme has been successfully implemented in our manufacturing flow for FEOL (Front-End-of-Line) application. This work investigated the application of tri-layer scheme to BEOL (Back-End-of-Line) AlCu patterning. One critical problem met in this application is the defect that majorly originates from wafer edge after AlCu patterning. The defects were finally ascribed to the hump formation of Si-rich hard-mask by EBR (Edge Bead Removal) process. The hump of Si-rich hard-mask yields etch masking behavior during AlCu etch accordingly leads to pattern bridging or peeling of inorganic hard-mask after AlCu patterning. To reduce the defect, several evaluations were made to suppress the hump formation, including the EBR optimization, bake condition of Si-rich hard-mask, film stacking architecture of tri-layer by EBR rinse and surfactant additive added Si-rich hard-mask. A synergy effect among process factors has been proposed to effectively fix the defect problem around wafer edge.

  10. Molded, wafer level optics for long wave infra-red applications

    Science.gov (United States)

    Franks, John

    2016-05-01

    For many years, the Thermal Imaging market has been driven by the high volume consumer market. The first signs of this came with the launch of night vision systems for cars, first by Cadillac and Honda and then, more successfully by BMW, Daimler and Audi. For the first time, simple thermal imaging systems were being manufactured at the rate of more than 10,000 units a year. This step change in volumes enabled a step change in system costs, with thermal imaging moving into the consumer's price range. Today we see that the consumer awareness and the consumer market continues to increase with the launch of a number of consumer focused smart phone add-ons. This has brought a further step change in system costs, with the possibility to turn your mobile phone into a thermal imager for under $250. As the detector technology has matured, the pixel pitches have dropped from 50μm in 2002 to 12 μm or even 10μm in today's detectors. This dramatic shrinkage in size has had an equally dramatic effect on the optics required to produce the image on the detector. A moderate field of view that would have required a focal length of 40mm in 2002 now requires a focal length of 8mm. For wide field of view applications and small detector formats, focal lengths in the range 1mm to 5mm are becoming common. For lenses, the quantity manufactured, quality and costs will require a new approach to high volume Infra-Red (IR) manufacturing to meet customer expectations. This, taken with the SwaP-C requirements and the emerging requirement for very small lenses driven by the new detectors, suggests that wafer scale optics are part of the solution. Umicore can now present initial results from an intensive research and development program to mold and coat wafer level optics, using its chalcogenide glass, GASIR®.

  11. Nanoscale x-ray imaging of circuit features without wafer etching.

    Science.gov (United States)

    Deng, Junjing; Hong, Young Pyo; Chen, Si; Nashed, Youssef S G; Peterka, Tom; Levi, Anthony J F; Damoulakis, John; Saha, Sayan; Eiles, Travis; Jacobsen, Chris

    2017-03-01

    Modern integrated circuits (ICs) employ a myriad of materials organized at nanoscale dimensions, and certain critical tolerances must be met for them to function. To understand departures from intended functionality, it is essential to examine ICs as manufactured so as to adjust design rules, ideally in a non-destructive way so that imaged structures can be correlated with electrical performance. Electron microscopes can do this on thin regions, or on exposed surfaces, but the required processing alters or even destroys functionality. Microscopy with multi-keV x-rays provides an alternative approach with greater penetration, but the spatial resolution of x-ray imaging lenses has not allowed one to see the required detail in the latest generation of ICs. X-ray ptychography provides a way to obtain images of ICs without lens-imposed resolution limits, with past work delivering 20-40 nm resolution on thinned ICs. We describe a simple model for estimating the required exposure, and use it to estimate the future potential for this technique. Here we show for the first time that this approach can be used to image circuit detail through an unprocessed 300 μ m thick silicon wafer, with sub-20 nm detail clearly resolved after mechanical polishing to 240 μ m thickness was used to eliminate image contrast caused by Si wafer surface scratches. By using continuous x-ray scanning, massively parallel computation, and a new generation of synchrotron light sources, this should enable entire non-etched ICs to be imaged to 10 nm resolution or better while maintaining their ability to function in electrical tests.

  12. Wafer-Level Packaging Method for RF MEMS Applications Using Pre-Patterned BCB Polymer

    Directory of Open Access Journals (Sweden)

    Zhuhao Gong

    2018-02-01

    Full Text Available A radio-frequency micro-electro-mechanical system (RF MEMS wafer-level packaging (WLP method using pre-patterned benzo-cyclo-butene (BCB polymers with a high-resistivity silicon cap is proposed to achieve high bonding quality and excellent RF performance. In this process, the BCB polymer was pre-defined to form the sealing ring and bonding layer by the spin-coating and patterning of photosensitive BCB before the cavity formation. During anisotropic wet etching of the silicon wafer to generate the housing cavity, the BCB sealing ring was protected by a sputtered Cr/Au (chromium/gold layer. The average measured thickness of the BCB layer was 5.9 μm. In contrast to the conventional methods of spin-coating BCB after fabricating cavities, the pre-patterned BCB method presented BCB bonding layers with better quality on severe topography surfaces in terms of increased uniformity of thickness and better surface flatness. The observation of the bonded layer showed that no void or gap formed on the protruding coplanar waveguide (CPW lines. A shear strength test was experimentally implemented as a function of the BCB widths in the range of 100–400 μm. The average shear strength of the packaged device was higher than 21.58 MPa. A RF MEMS switch was successfully packaged using this process with a negligible impact on the microwave characteristics and a significant improvement in the lifetime from below 10 million to over 1 billion. The measured insertion loss of the packaged RF MEMS switch was 0.779 dB and the insertion loss deterioration caused by the package structure was less than 0.2 dB at 30 GHz.

  13. Perineal wound complications after abdominoperineal resection.

    Science.gov (United States)

    Wiatrek, Rebecca L; Thomas, J Scott; Papaconstantinou, Harry T

    2008-02-01

    Perineal wound complications following abdominoperineal resection (APR) is a common occurrence. Risk factors such as operative technique, preoperative radiation therapy, and indication for surgery (i.e., rectal cancer, anal cancer, or inflammatory bowel disease [IBD]) are strong predictors of these complications. Patient risk factors include diabetes, obesity, and smoking. Intraoperative perineal wound management has evolved from open wound packing to primary closure with closed suctioned transabdominal pelvic drains. Wide excision is used to gain local control in cancer patients, and coupled with the increased use of pelvic radiation therapy, we have experienced increased challenges with primary closure of the perineal wound. Tissue transfer techniques such as omental pedicle flaps, and vertical rectus abdominis and gracilis muscle or myocutaneous flaps are being used to reconstruct large perineal defects and decrease the incidence of perineal wound complications. Wound failure is frequently managed by wet to dry dressing changes, but can result in prolonged hospital stay, hospital readmission, home nursing wound care needs, and the expenditure of significant medical costs. Adjuvant therapies to conservative wound care have been suggested, but evidence is still lacking. The use of the vacuum-assisted closure device has shown promise in chronic soft tissue wounds; however, experience is lacking, and is likely due to the difficulty in application techniques.

  14. Fabrication of Through via Holes in Ultra-Thin Fused Silica Wafers for Microwave and Millimeter-Wave Applications

    Directory of Open Access Journals (Sweden)

    Xiao Li

    2018-03-01

    Full Text Available Through via holes in fused silica are a key infrastructure element of microwave and millimeter-wave circuits and 3D integration. In this work, etching through via holes in ultra-thin fused silica wafers using deep reactive-ion etching (DRIE and laser ablation was developed and analyzed. The experimental setup and process parameters for both methods are presented and compared. For DRIE, three types of mask materials including KMPR 1035 (Nippon Kayaku, Tokyo, Japan photoresist, amorphous silicon and chromium—with their corresponding optimized processing recipes—were tested, aiming at etching through a 100 μm fused silica wafer. From the experiments, we concluded that using chromium as the masking material is the best choice when using DRIE. However, we found that the laser ablation method with a laser pulse fluence of 2.89 J/cm2 and a pulse overlap of 91% has advantages over DRIE. The laser ablation method has a simpler process complexity, while offering a fair etching result. In particular, the sidewall profile angle is measured to be 75° to the bottom surface of the wafer, which is ideal for the subsequent metallization process. As a demonstration, a two-inch wafer with 624 via holes was processed using both technologies, and the laser ablation method showed better efficiency compared to DRIE.

  15. N-type high-performance multicrystalline and mono-like silicon wafers with lifetimes above 2 ms

    Science.gov (United States)

    Pheng Phang, Sieu; Cheong Sio, Hang; Yang, Chia-Fu; Lan, Chung-Wen; Yang, Yu-Min; Wen-Huai Yu, Andy; Sung-Lin Hsu, Bruce; Wen-Ching Hsu, Chuck; Macdonald, Daniel

    2017-08-01

    Combined with advanced crystal growth technology and reduced dislocation densities, the higher tolerance to metal contamination of n-type silicon makes n-type cast-grown silicon a potential option for low cost high quality substrates for solar cells. Using a combination of photoconductance based lifetime testing and photoluminescence imaging, we have investigated the carrier lifetime in wafers from the bottom, middle, and top parts of a n-type high-performance multicrystalline (HPM) silicon ingot, and wafers from n-type mono-like silicon ingots after each high temperature solar cell processes, including after boron diffusion, phosphorus diffusion, and hydrogenation. Although boron diffusion leads to a degradation of the sample lifetime, phosphorus diffusion and hydrogenation is effective at recovering the lifetime in the intra-grain region and at the grain boundaries respectively. Quasi-steady-state photoconductance (QSSPC) measurements show that the arithmetic average lifetime of HPM silicon wafers and mono-like silicon wafers can reach up to 1.8 and 3.3 ms respectively for a process sequence including a boron diffusion, with corresponding implied open circuit voltage of about 720 mV. If the boron diffusion can be avoided, average lifetimes up to 3.0 and 6.6 ms can be achieved respectively, highlighting the excellent potential of n-type cast-grown materials.

  16. Investigation of Surface Pre-Treatment Methods for Wafer-Level Cu-Cu Thermo-Compression Bonding

    Directory of Open Access Journals (Sweden)

    Koki Tanaka

    2016-12-01

    Full Text Available To increase the yield of the wafer-level Cu-Cu thermo-compression bonding method, certain surface pre-treatment methods for Cu are studied which can be exposed to the atmosphere before bonding. To inhibit re-oxidation under atmospheric conditions, the reduced pure Cu surface is treated by H2/Ar plasma, NH3 plasma and thiol solution, respectively, and is covered by Cu hydride, Cu nitride and a self-assembled monolayer (SAM accordingly. A pair of the treated wafers is then bonded by the thermo-compression bonding method, and evaluated by the tensile test. Results show that the bond strengths of the wafers treated by NH3 plasma and SAM are not sufficient due to the remaining surface protection layers such as Cu nitride and SAMs resulting from the pre-treatment. In contrast, the H2/Ar plasma–treated wafer showed the same strength as the one with formic acid vapor treatment, even when exposed to the atmosphere for 30 min. In the thermal desorption spectroscopy (TDS measurement of the H2/Ar plasma–treated Cu sample, the total number of the detected H2 was 3.1 times more than the citric acid–treated one. Results of the TDS measurement indicate that the modified Cu surface is terminated by chemisorbed hydrogen atoms, which leads to high bonding strength.

  17. Investigation of the heating behavior of carbide-bonded graphene coated silicon wafer used for hot embossing

    Science.gov (United States)

    Yang, Gao; Li, Lihua; Lee, Wing Bun; Ng, Man Cheung; Chan, Chang Yuen

    2018-03-01

    A recently developed carbide-bonded graphene (CBG) coated silicon wafer was found to be an effective micro-patterned mold material for implementing rapid heating in hot embossing processes owing to its superior electrical and thermal conductivity, in addition to excellent mechanical properties. To facilitate the achievement of precision temperature control in the hot embossing, the heating behavior of a CBG coated silicon wafer sample was experimentally investigated. First, two groups of controlled experiments were conducted for quantitatively evaluating the influence of the main factors such as the vacuum pressure and gaseous environment (vacuum versus nitrogen) on its heating performance. The electrical and thermal responses of this sample under a voltage of 60 V were then intensively analyzed, and revealed that it had somewhat semi-conducting properties. Further, we compared its thermal profiles under different settings of the input voltage and current limiting threshold. Moreover, the strong temperature dependence of electrical resistance for this material was observed and determined. Ultimately, the surface temperature of CBG coated silicon wafer could be as high as 1300 ℃, but surprisingly the graphene coating did not detach from the substrate under such an elevated temperature due to its strong thermal coupling with the silicon wafer.

  18. The influence of silicon wafer thickness on characteristics of multijunction solar cells with vertical p—n-junctions

    Directory of Open Access Journals (Sweden)

    Gnilenko A. B.

    2012-02-01

    Full Text Available A multijunction silicon solar cell with vertical p–n junctions consisted of four serial n+–p–p+-structures was simulated using Silvaco TCAD software package. The dependence of solar cell characteristics on the silicon wafer thickness is investigated for a wide range of values.

  19. Robust Wafer-Level Thin-Film Encapsulation (Packaging) of Microstructures (MEMS) using Low Stress PECVD Silicon Carbide

    NARCIS (Netherlands)

    Rajaraman, V.; Pakula, L.S.; Pham, H.T.M.; Sarro, P.M.; French, P.J.

    2009-01-01

    This paper presents a new low-cost, CMOS-compatible and robust wafer-level encapsulation technique developed using a stress-optimised PECVD SiC as the capping and sealing material, imparting harsh environment capability. This technique has been applied for the fabrication and encapsulation of a wide

  20. Hepatic resection is associated with reduced postoperative opioid requirement

    Directory of Open Access Journals (Sweden)

    Caitlyn Rose Moss

    2016-01-01

    Conclusion: Patients undergoing open hepatic resection had a significantly lower opioid requirement in comparison with patients undergoing open pancreaticoduodenectomy. A multicenter prospective evaluation should be performed to confirm these findings.

  1. [Endoscopic modified technique of ureteral resection during nephroureterectomy].

    Science.gov (United States)

    Aguirre Benites, F; Blanco Carballo, O; Pamplona Casamayor, M; Díaz González, R; Leiva Galvis, O

    2007-01-01

    We show a technical modification of the ureteral endoscopic resection with which we try to avoid comunication between urine and surgical bed in order to prevent tumor local spread of upper urotelial tumor.

  2. Preoperative gemcitabine-based chemoradiation therapy for resectable pancreatic cancer

    International Nuclear Information System (INIS)

    Takahashi, Hidenori; Ohigashi, Hiroaki; Goto, Kunihito; Marubashi, Shigeru; Yano, Masahiko; Ishikawa, Osamu

    2013-01-01

    During the period from 2002 to 2011, a total of 240 consecutive patients with resectable pancreatic cancer received preoperative chemoradiation therapy (CRT). Among 240 patients, 201 patients underwent the subsequent pancreatectomy (resection rate: 84%). The 5-year overall survival of resected cases was 56% and the median survival of 39 unresected cases was 11 months. The 5-year locoregional recurrence rate of resected cases was 15%. The 5-year overall survival of the entire cohort (n=240) was 47%. The preoperative CRT and subsequent pancreatectomy provided a favorable surgical result, which was contributed by several characteristics of preoperative CRT: the prominent locoregional treatment effect with lower incidence of locoregional recurrence, and the discrimination between patients who are likely to benefit from subsequent surgery and those who are not. (author)

  3. Endoscopic resection of advanced and laterally spreading duodenal papillary tumors.

    Science.gov (United States)

    Klein, Amir; Tutticci, Nicholas; Bourke, Michael J

    2016-03-01

    Historically, neoplasia of the duodenal papilla has been managed surgically, which may be associated with substantial morbidity and mortality. In the absence of invasive cancer, even lesions with extensive lateral duodenal wall involvement, or limited intraductal extension may be cured endoscopically with a superior safety profile. Endoscopic papillectomy is associated with greater risks of adverse events such as bleeding than resection elsewhere in the gastrointestinal tract. Additionally site-specific complications such as pancreatitis exist. A structured approach to lesion assessment, adherence to technical aspects of resection, endoscopic management of complications and post-resection surveillance is required. Advances have been made in all facets of endoscopic papillary resection since its introduction in the 1980s; extending the boundaries of endoscopic cure, optimizing outcomes and enhancing patient safety. These will be the focus of the present review. © 2015 Japan Gastroenterological Endoscopy Society.

  4. Laparoscopic resection of a gastric schwannoma: A case report

    Directory of Open Access Journals (Sweden)

    Edgar Vargas Flores

    2016-01-01

    Conclusion: Gastric schwannomas should be included in the differential diagnosis of any gastric submucosal mass. Negative margin resection as seen with this patient is the standard surgical treatment as there is low malignant transformation potential.

  5. Robot-assisted segmental resection for intralobar pulmonary sequestration

    Directory of Open Access Journals (Sweden)

    J. Konecna

    2016-01-01

    Conclusion: We highlight the role of robotic technology offering three-dimensional view and excellent dexterity enhancing the surgical performance and getting the surgical procedure more precise and safer. This could be useful especially in case of challenging sublobar resections.

  6. 3D-printed guiding templates for improved osteosarcoma resection.

    Science.gov (United States)

    Ma, Limin; Zhou, Ye; Zhu, Ye; Lin, Zefeng; Wang, Yingjun; Zhang, Yu; Xia, Hong; Mao, Chuanbin

    2016-03-21

    Osteosarcoma resection is challenging due to the variable location of tumors and their proximity with surrounding tissues. It also carries a high risk of postoperative complications. To overcome the challenge in precise osteosarcoma resection, computer-aided design (CAD) was used to design patient-specific guiding templates for osteosarcoma resection on the basis of the computer tomography (CT) scan and magnetic resonance imaging (MRI) of the osteosarcoma of human patients. Then 3D printing technique was used to fabricate the guiding templates. The guiding templates were used to guide the osteosarcoma surgery, leading to more precise resection of the tumorous bone and the implantation of the bone implants, less blood loss, shorter operation time and reduced radiation exposure during the operation. Follow-up studies show that the patients recovered well to reach a mean Musculoskeletal Tumor Society score of 27.125.

  7. Laparoscopic resection for low rectal cancer: evaluation of oncological efficacy.

    LENUS (Irish Health Repository)

    Moran, Diarmaid C

    2011-09-01

    Laparoscopic resection of low rectal cancer poses significant technical difficulties for the surgeon. There is a lack of published follow-up data in relation to the surgical, oncological and survival outcomes in these patients.

  8. Thoracoscopic pulmonary wedge resection without post-operative chest drain

    DEFF Research Database (Denmark)

    Holbek, Bo Laksafoss; Hansen, Henrik Jessen; Kehlet, Henrik

    2016-01-01

    OBJECTIVE: Chest drains are used routinely after wedge resection by video-assisted thoracoscopic surgery (VATS), although this practice is based largely on tradition rather than evidence. Chest drains may furthermore cause pain, infections, and prolonged length of stay. The aim of this prospective...... observational study was to assess the feasibility of avoiding chest drains following VATS wedge resection for pulmonary nodules. METHODS: Between 1 February and 25 August 2015 166 consecutive patients planned for VATS wedge resection of pulmonary nodules were screened for inclusion using the following criteria...... effusion and coagulopathy. Chest X-rays were done twice on the day of surgery. 30-day complications were compiled from patient records. RESULTS: 49 patients underwent 51 unilateral VATS wedge resections without using a post-operative chest drain. No patient required reinsertion of a chest drain. 30 (59...

  9. [Functional condition of gallbladder after stomach resection by Roux].

    Science.gov (United States)

    Kuzin, N M; Kanadashvili, O V; Ivanova, Iu V

    2000-01-01

    This study examined the results of surgical treatment of 90 patients with ulcerative stenosing disease of the stomach and duodenal ulcer between 1984 and 1995. 30 patients (study group) underwent stomach Roux resection. Truncal vagotomy with stomach Bilroth-I resection (control group) was made in 20 patients, 20 patients had a truncal vagotomy with pyloroplasty according to Heineke-Mikulicz (control group), and 20 patients had a selective proximal vagotomy with gastroduodenostomy by Joboulay (control group). Motor and evacuation functions of gallbladder were assessed by dynamic US and radioisotope scintigraphy. After a Roux stomach resection and a stomach Bilroth-I resection, respectively, hypokinetic and hyperkinetic types of the gallbladder's dyskinesia was established. After a selective proximal vagotomy with gastroduodenostomy by Joboulay and truncal vagotomy with pyloroplasty according to Heineke-Mikulicz essential change of the gallbladder refractive function wasn't observed.

  10. An alternative treatment for anastomotic leakage after oesophageal resection

    DEFF Research Database (Denmark)

    Damm, P; Hoffmann, J.

    1988-01-01

    An alternative non-operative method for treatment for anastomotic leakage after oesophageal resection is presented. A mediastinal abscess cavity was drained by an ordinary nasogastric tube introduced via the nose through the anastomotic defect and into the cavity.......An alternative non-operative method for treatment for anastomotic leakage after oesophageal resection is presented. A mediastinal abscess cavity was drained by an ordinary nasogastric tube introduced via the nose through the anastomotic defect and into the cavity....

  11. Transurethral resection of prostate syndrome: report of a case

    OpenAIRE

    Boukatta, Brahim; Sbai, Hicham; Messaoudi, Ferdaous; Lafrayiji, Zakaria; El Bouazzaoui, Abderrahim; Kanjaa, Nabil

    2013-01-01

    We report a case of transurethral resection of prostate (TURP) syndrome. A 78-year-old man with prostatic hypertrophy was scheduled for transurethral resection of the prostate under spinal anesthesia. 30 minutes after the end of the surgery, the patient presented signs of TURP syndrome with bradycardia, arterial hypotension, cyanosis, hypoxemia and coma. The electrolytes analysis revealed an acute hyponatremia (sodium concentration 125 mmol/L). Medical treatment consisted of hypertonic saline...

  12. Robot-assisted segmental resection for intralobar pulmonary sequestration

    OpenAIRE

    J. Konecna; W. Karenovics; G. Veronesi; F. Triponez

    2016-01-01

    Introduction: Pulmonary sequestration is a rare congenital malformation found most frequently as intralobar sequestration in the left lower lobe. Complete surgical resection is considered the treatment of choice. Presentation: We present the case of a 29- year-old woman with intralobar pulmonary sequestration (ILS) diagnosed on chest CT. The sequestration was located in the left lower basal segments (segments 9 and 10) and was treated successfully by robot-assisted segmental resection with...

  13. HYSTEROSCOPIC RESECTION OF UTERINE SEPTUM – EFFECTS ON PREGNANCY

    Directory of Open Access Journals (Sweden)

    Helena Ban

    2003-12-01

    Full Text Available Background. In women with spontaneous abortions, preterm deliveries or infertility, septate uterus is often detected on transvaginal ultrasound examination. Since 1993 we have used hysteroscopic resection to correct this anomaly. The aim of this study was to evaluate the effect of the arcuate uterus on the course of pregnancy and its outcome, and the effect of hysteroscopic resection of the arcuate uterus on the prognosis of pregnancy.Patients and methods. Retrospectively we analyzed prospectively collected data. Between 15 February 1993 and 31 December 1999 we performed 760 hysteroscopic resections of the septum at the Department of Obstetrics and Gynecology in Ljubljana. We evaluated the course of pregnancy and its outcome only, therefore we enrolled 241 women, who conceived spontaneously before and after operation.Results. In the group of women with arcuate uterus (n = 111 there were 244 pregnancies before hysteroscopic resection: 38 (15.6% ended with a delivery and 202 (82.8% with a spontaneous abortion. In the group of women with septate uterus (n = 130 there were 269 pregnancies: 42 deliveries (15.6% and 224 (83.3% spontaneous abortions. After hysteroscopic resection there were 109 pregnancies in the women with arcuate uterus: 91 (83.5% deliveries and 16 (14.7% spontaneous abortions; in the septate uterus group there were 118 pregnancies: 98 (83.2% deliveries and 16 (13.5% spontaneous abortions. In both groups there was a significant improvement in the delivery rate (p < 0.00000. Before resection the preterm delivery rates were significantly higher in both groups (arcuate: 50.0%; septate: 35.1% than after the resection (arcuate: 11.3%; septate 17.7%.Conclusions. The women with either septate or arcuate uterus are at a higher risk for spontaneous abortion and preterm delivery. Hysteroscopic resection significantly decreases the risk in both groups of women.

  14. Transanal stent in anterior resection does not prevent anastomotic leakage

    DEFF Research Database (Denmark)

    Bülow, Steffen; Bulut, O; Christensen, Ib Jarle

    2006-01-01

    OBJECTIVE: A defunctioning transanal stent may theoretically reduce the leakage rate after anterior rectal resection. We present a randomized open study with the aim of comparing the leakage rate after anterior resection with a loop ileostomy, a transanal stent, both or neither. PATIENTS AND METH....... On this basis it was decided to discontinue the study prematurely for ethical reasons. CONCLUSION: Decompression of the anastomosis with a transanal stent does not reduce the risk of anastomotic leakage after anterior resection.......OBJECTIVE: A defunctioning transanal stent may theoretically reduce the leakage rate after anterior rectal resection. We present a randomized open study with the aim of comparing the leakage rate after anterior resection with a loop ileostomy, a transanal stent, both or neither. PATIENTS...... AND METHODS: Randomized open trial of 194 patients operated in 11 hospitals during September 2000 to September 2003 with anterior resection for a mobile rectal tumour, 115 men and 79 women, median age 68 years (range 37-90 years). The surgeon decided upon the use of a protective ileostomy, and after...

  15. Is routine abdominal drainage necessary after liver resection?

    Science.gov (United States)

    Wada, Seidai; Hatano, Etsuro; Yoh, Tomoaki; Seo, Satoru; Taura, Kojiro; Yasuchika, Kentaro; Okajima, Hideaki; Kaido, Toshimi; Uemoto, Shinji

    2017-06-01

    Prophylactic abdominal drainage is performed routinely after liver resection in many centers. The aim of this study was to examine the safety and validity of liver resection without abdominal drainage and to clarify whether routine abdominal drainage after liver resection is necessary. Patients who underwent elective liver resection without bilio-enteric anastomosis between July, 2006 and June, 2012 were divided into two groups, based on whether surgery was performed before or after, we adopted the no-drain strategy. The "former group" comprised 256 patients operated on between July, 2006 and June, 2009 and the "latter group" comprised 218 patients operated between July, 2009 and June, 2012. We compared the postoperative complications, percutaneous drainage, and postoperative hospital stay between the groups, retrospectively. There were no significant differences in the rates of postoperative bleeding, intraabdominal infection, or bile leakage between the groups. Drain insertion after liver resection did not reduce the rate of percutaneous drainage. Postoperative hospital stay was significantly shorter in the latter group. Routine abdominal drainage is unnecessary after liver resection without bilio-enteric anastomosis.

  16. Management of a large mucosal defect after duodenal endoscopic resection.

    Science.gov (United States)

    Fujihara, Shintaro; Mori, Hirohito; Kobara, Hideki; Nishiyama, Noriko; Matsunaga, Tae; Ayaki, Maki; Yachida, Tatsuo; Masaki, Tsutomu

    2016-08-07

    Duodenal endoscopic resection is the most difficult type of endoscopic treatment in the gastrointestinal tract (GI) and is technically challenging because of anatomical specificities. In addition to these technical difficulties, this procedure is associated with a significantly higher rate of complication than endoscopic treatment in other parts of the GI tract. Postoperative delayed perforation and bleeding are hazardous complications, and emergency surgical intervention is sometimes required. Therefore, it is urgently necessary to establish a management protocol for preventing serious complications. For instance, the prophylactic closure of large mucosal defects after endoscopic resection may reduce the risk of hazardous complications. However, the size of mucosal defects after endoscopic submucosal dissection (ESD) is relatively large compared with the size after endoscopic mucosal resection, making it impossible to achieve complete closure using only conventional clips. The over-the-scope clip and polyglycolic acid sheets with fibrin gel make it possible to close large mucosal defects after duodenal ESD. In addition to the combination of laparoscopic surgery and endoscopic resection, endoscopic full-thickness resection holds therapeutic potential for difficult duodenal lesions and may overcome the disadvantages of endoscopic resection in the near future. This review aims to summarize the complications and closure techniques of large mucosal defects and to highlight some directions for management after duodenal endoscopic treatment.

  17. Ileocolic junction resection in dogs and cats: 18 cases.

    Science.gov (United States)

    Fernandez, Yordan; Seth, Mayank; Murgia, Daniela; Puig, Jordi

    2017-12-01

    There is limited veterinary literature about dogs or cats with ileocolic junction resection and its long-term follow-up. To evaluate the long-term outcome in a cohort of dogs and cats that underwent resection of the ileocolic junction without extensive (≥50%) small or large bowel resection. Medical records of dogs and cats that had the ileocolic junction resected were reviewed. Follow-up information was obtained either by telephone interview or e-mail correspondence with the referring veterinary surgeons. Nine dogs and nine cats were included. The most common cause of ileocolic junction resection was intussusception in dogs (5/9) and neoplasia in cats (6/9). Two dogs with ileocolic junction lymphoma died postoperatively. Only 2 of 15 animals, for which long-term follow-up information was available, had soft stools. However, three dogs with suspected chronic enteropathy required long-term treatment with hypoallergenic diets alone or in combination with medical treatment to avoid the development of diarrhoea. Four of 6 cats with ileocolic junction neoplasia were euthanised as a consequence of progressive disease. Dogs and cats undergoing ileocolic junction resection and surviving the perioperative period may have a good long-term outcome with mild or absent clinical signs but long-term medical management may be required.

  18. Minimally Invasive Approach for Resection of Parameningeal Rhabdomyosarcoma.

    Science.gov (United States)

    Wertz, Aileen; Tillman, Brittny N; Brinkmeier, Jennifer V; Glazer, Tiffany A; Kroeker, Andrew D; Sullivan, Steven E; McKean, Erin L

    2017-06-01

    Background  About one-third of rhabdomyosarcomas arise in the head and neck, with parameningeal primaries accounting for half of these. Principles of management involve chemotherapy, radiation, or both, in addition to surgical biopsy, debulking, and complete or near-complete resection. In the head and neck, diagnostic biopsies have historically been performed without attempt at resection due to proximity to critical structures and cosmetic considerations. Methods  Retrospective chart review of three cases of rhabdomyosarcoma at the cranial base managed through minimally invasive endoscopic surgical resection and adjuvant therapy. Results  Three patients were identified as having undergone endoscopic surgical debulking or margin-negative resection of a rhabdomyosarcoma of the cranial base. Two of three patients had complete resection based on intraoperative margin control. All three patients underwent adjuvant therapy within 1 month of diagnosis. Follow-up time ranged from 5 months to 3 years with all patients disease-free at last follow-up. Conclusion  Skull base surgeons should routinely be involved in multidisciplinary treatment planning for parameningeal rhabdomyosarcomas, as surgical options have evolved to allow for potential endoscopic resection with low morbidity and no or minimal delay in additional treatment options.

  19. Bilateral carotid body tumor resection in a female patient

    Directory of Open Access Journals (Sweden)

    Alfred Burgess

    Full Text Available Introduction: Carotid body tumors also called carotid paragangliomas are rare neuroendocrine neoplasms derived from neural crest cells, approximately 3% of all paragangliomas occur in the head and neck area (Xiao and She, 2015; although they represent 65% of the head and neck paragangliomas (Georgiadis et al., 2008. Presentation of case: We present the therapeutic management of a 65-year-old woman with bilateral carotid body tumors. The patient presented to medical clinic for unrelated signs and symptoms of weight loss, dyspepsia, and epigastric pain. Physical examination showed bilateral non-tender neck masses for which imaging studies were ordered resulting in the diagnosis of bilateral carotid tumor. Surgical resection was staged with one week of distance between each tumor resection. Discussion: Carotid Body Tumors can arise from the paraganglia located within the adventitia of the medial aspect of the carotid bifurcation.Resection is the only curative treatment. Carotid body tumors resection represents a special challenge due to potential neurovascular complications. Conclusions: Surgical resection of carotid body tumors represents a special challenge to the surgeon because of the complex anatomical location of the tumor, including close relationship with the cranial nerves, involvement of the carotid vessels and large vascularization of the tumor. With the advance of diagnosis and improvement in surgical techniques as well as the understanding of biological behavior of tumors, surgical treatment has become a safer alternative for treating these tumors. Keywords: Carotid body tumor, Bilateral, Paraganglioma, Resection

  20. Laparoscopic left colon resection for diverticular disease.

    Science.gov (United States)

    Trebuchet, G; Lechaux, D; Lecalve, J L

    2002-01-01

    The aim of this study was to review our experience with laparoscopic sigmoid colectomy for diverticular disease. All patients presenting with acute or chronic diverticulitis, obstruction, abscess, or fistula were included. Symptomatic diverticular disease was the main surgical indication (95%). Between March 1992 and August 1999 170 consecutive patients underwent surgery. Of these, 21 patients (12%) had significant obesity, with body mass index (BMI) greater than 30. The average length of surgery was 141 +/- 36 min. In 163 patients (96%), the procedure was performed solely with the laparoscope. The nasogastric tube was removed on postoperative day 2 +/- 1.9, and oral feeding was started on postoperative day 3.4 +/- 2.1. The average length of hospital stay after surgery was 8.5 +/- 3.7 days. During the first postoperative month, there were no deaths. However, 11 patients (6.5%) had surgical complications: 5 anastomotic leaks (2.9%), 1 intraabdominal abscess (0.6%), and 3 wound infections (1.7%). There were four reinterventions (2.4%), with two diverting colostomies. Secondarily, 10 anastomotic stenoses (5.9%) were observed. Eight patients required a reintervention: seven anastomotic resections by open laparotomy and one terminal colostomy. Seven patients (4.1%) reported retrograde ejaculation, and one reported impotence. The feasibility of the laparoscopic approach to diverticular disease is established with a conversion rate of 4%, a low incidence of acute septic complications (5.3%), and a mortality rate of 0%. Therefore, laparoscopic sigmoid colectomy has become our procedure of choice in the treatment of diverticular disease.

  1. Intersphincteric Resection and Coloanal Anastomosis in Treatment of Distal Rectal Cancer

    Directory of Open Access Journals (Sweden)

    Gokhan Cipe

    2012-01-01

    Full Text Available In the treatment of distal rectal cancer, abdominoperineal resection is traditionally performed. However, the recognition of shorter safe distal resection line, intersphincteric resection technique has given a chance of sphincter-saving surgery for patients with distal rectal cancer during last two decades and still is being performed as an alternative choice of abdominoperineal resection. The first aim of this study is to assess the morbidity, mortality, oncological, and functional outcomes of intersphincteric resection. The second aim is to compare outcomes of patients who underwent intersphincteric resection with the outcomes of patients who underwent abdominoperineal resection.

  2. Late morbidity after duodenum-preserving pancreatic head resection with bile duct reinsertion into the resection cavity.

    Science.gov (United States)

    Cataldegirmen, G; Bogoevski, D; Mann, O; Kaifi, J T; Izbicki, J R; Yekebas, E F

    2008-04-01

    Reinsertion of the distal common bile duct (CBD) into the pancreatic resection cavity during duodenum-preserving pancreatic head excision (DPPHE) may be an alternative option to Whipple resection or bilioenteric anastomosis when chronic pancreatitis is associated with CBD stenosis. Outcome in 82 patients with chronic pancreatitis who underwent DPPHE with CBD reinsertion was compared with that in 432 who had DPPHE without reinsertion and 50 who had a Whipple procedure or pylorus-preserving pancreatoduodenectomy (PPPD). There were no deaths after DPPHE with CBD reinsertion, compared with four (0.9 per cent) after DPPHE without reinsertion and three (6 per cent) after classical resection. Overall morbidity rates were 30, 28.9 and 36 per cent respectively. Fifteen patients (18 per cent) who had DPPHE with CBD reinsertion developed a stricture at the reinsertion site, compared with a long-term stricture rate of 2.3 per cent (ten patients) after DPPHE without CBD reinsertion and 4 per cent (two patients) after PPPD/Whipple resection. Although associated with a high incidence of anastomotic stricture, reinsertion of the CBD into the resection cavity as part of DPPHE can be used to preserve duodenal passage and offers an alternative to extended resection for chronic pancreatitis. 2007 British Journal of Surgery Society Ltd. Published by John Wiley & Sons, Ltd.

  3. Effects of gas-flow structures on radical and etch-product density distributions on wafers in magnetomicrowave plasma etching reactors

    International Nuclear Information System (INIS)

    Ikegawa, Masato; Kobayashi, Jun'ichi; Fukuyama, Ryoji

    2001-01-01

    To achieve high etch rate, uniformity, good selectivity, and etch profile control across large diameter wafers, the distributions of ions, radicals, and etch products in magnetomicrowave high-etch-rate plasma etching reactors must be accurately controlled. In this work the effects of chamber heights, a focus ring around the wafer, and gas supply structures (or gas flow structures) on the radicals and etch products flux distribution onto the wafer were examined using the direct simulation Monte Carlo method and used to determine the optimal reactor geometry. The pressure uniformity on the wafer was less than ±1% when the chamber height was taller than 60 mm. The focus ring around the wafer produced uniform radical and etch-product fluxes but increased the etch-product flux on the wafer. A downward-flow gas-supply structure (type II) produced a more uniform radical distribution than that produced by a radial gas-supply structure (type I). The impact flow of the type II structure removed etch products from the wafer effectively and produced a uniform etch-product distribution even without the focus ring. Thus the downward-flow gas-supply structure (type II) was adopted in the design for the second-generation of a magnetomicrowave plasma etching reactor with a higher etching rate

  4. A randomized trial comparing multiband mucosectomy and cap-assisted endoscopic resection for endoscopic piecemeal resection of early squamous neoplasia of the esophagus

    NARCIS (Netherlands)

    Zhang, Yue-Ming; Boerwinkel, David F.; Qin, Xiumin; He, Shun; Xue, Liyan; Weusten, Bas L. A. M.; Dawsey, Sanford M.; Fleischer, David E.; Dou, Li-Zhou; Liu, Yong; Lu, Ning; Bergman, Jacques J. G. H. M.; Wang, Gui-Qi

    2016-01-01

    Piecemeal endoscopic resection for esophageal high grade intraepithelial neoplasia (HGIN) or early squamous cell carcinoma (ESCC) is usually performed by cap-assisted endoscopic resection. This requires submucosal lifting and multiple snares. Multiband mucosectomy (MBM) uses a modified variceal band

  5. In-situ wafer bowing measurements of GaN grown on Si (111) substrate by reflectivity mapping in metal organic chemical vapor deposition system

    Science.gov (United States)

    Yang, Yi-Bin; Liu, Ming-Gang; Chen, Wei-Jie; Han, Xiao-Biao; Chen, Jie; Lin, Xiu-Qi; Lin, Jia-Li; Luo, Hui; Liao, Qiang; Zang, Wen-Jie; Chen, Yin-Song; Qiu, Yun-Ling; Wu, Zhi-Sheng; Liu, Yang; Zhang, Bai-Jun

    2015-09-01

    In this work, the wafer bowing during growth can be in-situ measured by a reflectivity mapping method in the 3×2″ Thomas Swan close coupled showerhead metal organic chemical vapor deposition (MOCVD) system. The reflectivity mapping method is usually used to measure the film thickness and growth rate. The wafer bowing caused by stresses (tensile and compressive) during the epitaxial growth leads to a temperature variation at different positions on the wafer, and the lower growth temperature leads to a faster growth rate and vice versa. Therefore, the wafer bowing can be measured by analyzing the discrepancy of growth rates at different positions on the wafer. Furthermore, the wafer bowings were confirmed by the ex-situ wafer bowing measurement. High-resistivity and low-resistivity Si substrates were used for epitaxial growth. In comparison with low-resistivity Si substrate, GaN grown on high-resistivity substrate shows a larger wafer bowing caused by the highly compressive stress introduced by compositionally graded AlGaN buffer layer. This transition of wafer bowing can be clearly in-situ measured by using the reflectivity mapping method. Project supported by the National Natural Science Foundation of China (Grant Nos. 61274039 and 51177175), the National Basic Research Program of China (Grant No. 2011CB301903), the Ph.D. Programs Foundation of Ministry of Education of China (Grant No. 20110171110021), the International Science and Technology Collaboration Program of China (Grant No. 2012DFG52260), the International Science and Technology Collaboration Program of Guangdong Province, China (Grant No. 2013B051000041), the Science and Technology Plan of Guangdong Province, China (Grant No. 2013B010401013), the National High Technology Research and Development Program of China (Grant No. 2014AA032606), and the Opened Fund of the State Key Laboratory on Integrated Optoelectronics, China (Grant No. IOSKL2014KF17).

  6. Magnetic resonance imaging surveillance following vestibular schwannoma resection.

    Science.gov (United States)

    Carlson, Matthew L; Van Abel, Kathryn M; Driscoll, Colin L; Neff, Brian A; Beatty, Charles W; Lane, John I; Castner, Marina L; Lohse, Christine M; Link, Michael J

    2012-02-01

    To describe the incidence, pattern, and course of postoperative enhancement within the operative bed using serial gadolinium-enhanced magnetic resonance imaging (MRI) following vestibular schwannoma (VS) resection and to identify clinical and radiologic variables associated with recurrence. Retrospective cohort study. All patients who underwent microsurgical resection of VS between January 2000 and January 2010 at a single tertiary referral center were reviewed. Postoperative enhancement patterns were characterized on serial MRI studies. Clinical follow-up and outcomes were recorded. During the last 10 years, 350 patients underwent microsurgical VS resection, and of these, 203 patients met study criteria (mean radiologic follow-up, 3.5 years). A total of 144 patients underwent gross total resection (GTR), 32 received near-total resection (NTR), and the remaining 27 underwent subtotal resection (STR); 98.5% of patients demonstrated enhancement within the operative bed following resection (58.5% linear, 41.5% nodular). Stable enhancement patterns were seen in 24.5% of patients, regression in 66.0%, and resolution in only 3.5% of patients on the most recent postoperative MRI. Twelve patients recurred a mean of 3.0 years following surgery. The average maximum linear diameter growth rate among recurrent tumors was 2.3 mm per year. Those receiving STR were more than nine times more likely to experience recurrence compared to those undergoing NTR or GTR (P assist the clinician in determining an appropriate postoperative MRI surveillance schedule. Future studies using standardized terminology and consistent study metrics are needed to further refine surveillance recommendations. Copyright © 2011 The American Laryngological, Rhinological, and Otological Society, Inc.

  7. Complications of ventricular entry during craniotomy for brain tumor resection.

    Science.gov (United States)

    John, Jessin K; Robin, Adam M; Pabaney, Aqueel H; Rammo, Richard A; Schultz, Lonni R; Sadry, Neema S; Lee, Ian Y

    2017-08-01

    OBJECTIVE Recent studies have demonstrated that periventricular tumor location is associated with poorer survival and that tumor location near the ventricle limits the extent of resection. This finding may relate to the perception that ventricular entry leads to further complications and thus surgeons may choose to perform less aggressive resection in these areas. However, there is little support for this view in the literature. This study seeks to determine whether ventricular entry is associated with more complications during craniotomy for brain tumor resection. METHODS A retrospective analysis of patients who underwent craniotomy for tumor resection at Henry Ford Hospital between January 2010 and November 2012 was conducted. A total of 183 cases were reviewed with attention to operative entry into the ventricular system, postoperative use of an external ventricular drain (EVD), subdural hematoma, hydrocephalus, and symptomatic intraventricular hemorrhage (IVH). RESULTS Patients in whom the ventricles were entered had significantly higher rates of any complication (46% vs 21%). Complications included development of subdural hygroma, subdural hematoma, intraventricular hemorrhage, subgaleal collection, wound infection, urinary tract infection/deep venous thrombosis, hydrocephalus, and ventriculoperitoneal (VP) shunt placement. Specifically, these patients had significantly higher rates of EVD placement (23% vs 1%, p entry (11% vs 0%, p = 0.001) with 3 of 4 of these patients having a large ventricular entry (defined here as entry greater than a pinhole [entry). Furthermore, in a subset of glioblastoma patients with and without ventricular entry, Kaplan-Meier estimates for survival demonstrated a median survival time of 329 days for ventricular entry compared with 522 days for patients with no ventricular entry (HR 1.13, 95% CI 0.65-1.96; p = 0.67). CONCLUSIONS There are more complications associated with ventricular entry during brain tumor resection than in

  8. Reliability assessment of ultra-thin HfO2 films deposited on silicon wafer

    International Nuclear Information System (INIS)

    Fu, Wei-En; Chang, Chia-Wei; Chang, Yong-Qing; Yao, Chih-Kai; Liao, Jiunn-Der

    2012-01-01

    Highlights: ► Nano-mechanical properties on annealed ultra-thin HfO 2 film are studied. ► By AFM analysis, hardness of the crystallized HfO 2 film significantly increases. ► By nano-indention, the film hardness increases with less contact stiffness. ► Quality assessment on the annealed ultra-thin films can thus be achieved. - Abstract: Ultra-thin hafnium dioxide (HfO 2 ) is used to replace silicon dioxide to meet the required transistor feature size in advanced semiconductor industry. The process integration compatibility and long-term reliability for the transistors depend on the mechanical performance of ultra-thin HfO 2 films. The criteria of reliability including wear resistance, thermal fatigue, and stress-driven failure rely on film adhesion significantly. The adhesion and variations in mechanical properties induced by thermal annealing of the ultra-thin HfO 2 films deposited on silicon wafers (HfO 2 /SiO 2 /Si) are not fully understood. In this work, the mechanical properties of an atomic layer deposited HfO 2 (nominal thickness ≈10 nm) on a silicon wafer were characterized by the diamond-coated tip of an atomic force microscope and compared with those of annealed samples. The results indicate that the annealing process leads to the formation of crystallized HfO 2 phases for the atomic layer deposited HfO 2 . The HfSi x O y complex formed at the interface between HfO 2 and SiO 2 /Si, where the thermal diffusion of Hf, Si, and O atoms occurred. The annealing process increases the surface hardness of crystallized HfO 2 film and therefore the resistance to nano-scratches. In addition, the annealing process significantly decreases the harmonic contact stiffness (or thereafter eliminate the stress at the interface) and increases the nano-hardness, as measured by vertically sensitive nano-indentation. Quality assessments on as-deposited and annealed HfO 2 films can be thereafter used to estimate the mechanical properties and adhesion of ultra-thin HfO 2

  9. Prophylactic resection, uncomplicated diverticulitis, and recurrent diverticulitis.

    Science.gov (United States)

    Wolff, Bruce G; Boostrom, Sarah Y

    2012-01-01

    The classifications of acute uncomplicated diverticulitis and complicated diverticulitis have served us well for many years. However, in recent years, we have noted the prevalence of variations of uncomplicated diverticulitis, which have not precisely fit under the classification of 'acute resolving uncomplicated diverticulitis', which manifests itself with the typical left lower quadrant pain, fever, diarrhea, elevated white blood count, and CT findings, such as stranding, and which resolves fairly promptly and completely on oral antibiotic therapy. For these other variations, we would suggest we use the term chronic diverticulitis, as a subset of uncomplicated diverticulitis, meaning there is no abscess, stricture, or fistula, but the episode does not respond to the usual antibiotic treatment, and there is a rebound symptomatology once the treatment has stopped, or there is continuing subliminal inflammation that continues, typically, for several weeks after the initial episode without complete resolution. This variation could also be termed 'smoldering' diverticulitis. A second variation of uncomplicated diverticulitis should be termed atypical diverticulitis, since this variant does not manifest all of the usual components of acute diverticulitis, particularly an absence of fever, and even white blood count elevation, and there may be a lack of diagnostic evidence of acute diverticulitis. This diagnosis must be compared with diarrhea-predominant irritable bowel syndrome, and it is sometimes very difficult to distinguish between these two entities. The character of the pain in irritable bowel syndrome is typically cramping intermittently, compared with the more constant pain in smoldering diverticulitis. In our study by Horgan, McConnell, Wolff and coworkers, 5% of 930 patients who underwent sigmoid resection fit into this category of atypical uncomplicated diverticulitis. These 47 patients all had diverticulosis, and 76% that had surgery had evidence of acute

  10. Massive chest wall resection and reconstruction for malignant disease

    Science.gov (United States)

    Foroulis, Christophoros N; Kleontas, Athanassios D; Tagarakis, George; Nana, Chryssoula; Alexiou, Ioannis; Grosomanidis, Vasilis; Tossios, Paschalis; Papadaki, Elena; Kioumis, Ioannis; Baka, Sofia; Zarogoulidis, Paul; Anastasiadis, Kyriakos

    2016-01-01

    Objective Malignant chest wall tumors are rare neoplasms. Resection with wide-free margins is an important prognostic factor, and massive chest wall resection and reconstruction are often necessary. A recent case series of 20 consecutive patients is reported in order to find any possible correlation between tumor histology, extent of resection, type of reconstruction, and adjuvant treatment with short- and long-term outcomes. Methods Twenty patients were submitted to chest wall resection and reconstruction for malignant chest wall neoplasms between 2006 and 2014. The mean age (ten males) was 59±4 years. The size and histology of the tumor, the technique of reconstruction, and the short- and long-term follow-up records were noted. Results The median maximum diameter of tumors was 10 cm (5.4–32 cm). Subtotal sternal resection was performed in nine cases, and the resection of multiple ribs was performed in eleven cases. The median area of chest wall defect was 108 cm2 (60–340 cm2). Histology revealed soft tissue, bone, and cartilage sarcomas in 16 cases (80%), most of them chondrosarcomas. The rest of the tumors was metastatic tumors in two cases and localized malignant pleural mesothelioma and non-Hodgkin lymphoma in one case. The chest wall defect was reconstructed by using the “sandwich technique” (propylene mesh/methyl methacrylate/propylene mesh) in nine cases of large anterior defects or by using a 2 mm polytetrafluoroethylene (e-PTFE) mesh in nine cases of lateral or posterior defects. Support from a plastic surgeon was necessary to cover the full-thickness chest wall defects in seven cases. Adjuvant oncologic treatment was administered in 13 patients. Local recurrences were observed in five cases where surgical reintervention was finally necessary in two cases. Recurrences were associated with larger tumors, histology of malignant fibrous histiocytoma, and initial incomplete resection or misdiagnosis made by nonthoracic surgeons. Three patients died

  11. Resection and anastomosis of the descending colon in 43 horses.

    Science.gov (United States)

    Prange, Timo; Holcombe, Susan J; Brown, Jennifer A; Dechant, Julie E; Fubini, Susan L; Embertson, Rolf M; Peroni, John; Rakestraw, Peter C; Hauptman, Joe G

    2010-08-01

    To determine (1) the short- (to hospital discharge) and long- (>6 months) term survival, (2) factors associated with short-term survival, and (3) the perioperative course for horses with resection and anastomosis of the descending colon. Multicentered case series. Horses (n=43) that had descending colon resection and anastomosis. Medical records (January 1995-June 2009) of 7 equine referral hospitals were reviewed for horses that had descending colon resection and anastomosis and were recovered from anesthesia. Retrieved data included history, results of clinical and clinicopathologic examinations, surgical findings, postsurgical treatment and complications, and short-term survival (hospital discharge). Long-term survival was defined as survival > or =6 months after hospital discharge. Of 43 horses, 36 (84%) were discharged from the hospital. Twenty-eight of 30 horses with follow-up information survived > or =6 months. No significant associations between perioperative factors and short-term survival were identified. Lesions included strangulating lipoma (n=27), postfoaling trauma (4), infarction (4), intraluminal obstruction (2), and other (6). Common postoperative complications included fever and diarrhea. During hospitalization 7 horses were euthanatized or died because of septic peritonitis (3), endotoxemia (3), and colic and ileus (1). Descending colon resection and anastomosis has a favorable prognosis for hospital discharge and survival > or =6 months. The most common cause of small colon incarceration was strangulating lipoma. Complications include postoperative fever and diarrhea but the prognosis is good after small colon resection and anastomosis.

  12. Resection of peritoneal metastases causing malignant small bowel obstruction

    Directory of Open Access Journals (Sweden)

    Merrie Arend EH

    2007-10-01

    Full Text Available Abstract Background Resection of peritoneal metastases has been shown to improve survival in patients with abdominal metastatic disease from abdominal or extra abdominal malignancy. This study evaluates the benefit of peritoneal metastatic resection in patients with malignant small bowel obstruction and a past history of treated cancer. Patients and methods Patients undergoing laparotomy for resection of peritoneal metastases from recurrence of previous cancer between 1992–2003 were reviewed retrospectively. Data were collected about type of primary cancer, interval to recurrence, extent of the disease and completeness of resection, morbidity and mortality and long-term survival. Results Between 1992 and 2003 there were 79 patients (median age 62, range 19–91 who had laparotomy for small bowel obstruction due to recurrent cancer. The primary cancer was colorectal (31, gynaecologic cancer (19, melanoma (16 and others (13. Overall, the rate of complications was 35% and mortality was 10%. Median survival was 5 months; patients with history of colorectal cancer had better survival than other cancer (median survival 7 months vs. 4 months; p = 0.02. Multivariate analysis showed that the extent of recurrent disease was the only factor that affected overall survival. Conclusion Laparotomy for small bowel obstruction is a worthwhile option for patients with malignant small bowel obstruction. Although it is associated with significant morbidity and mortality it offers a reasonable survival benefit in particular for patients with completely resectable disease.

  13. [Laparoscopic liver resection using a radiofrequency dissector. Initial experience].

    Science.gov (United States)

    Croce, Enrico; Olmi, Stefano; Bertolini, Aimone; Erba, Luigi; Perego, Paolo; Magnone, Stefano

    2003-01-01

    Laparoscopic liver surgery, especially when resective, requires both the skill of an expert laparoscopist and the experience of a liver surgeon. The aims of the study were to assess the feasibility of minor laparoscopic liver resection by means of a radiofrequency dissector and to evaluate the laparoscopic approach. From January 1993 to November 2002 we carried out 7 laparoscopic liver resections (3 men, 4 women), 5 of which for benign diseases and 2 for metastases from colorectal cancer. In 4 of the above resections we used an argon coagulator, while the last 3 were performed using a radiofrequency instrument. We had no perioperative or postoperative complications in this small series of patients. The mean perioperative blood loss was 120 ml (range: 80-200) and the procedure took about 90 minutes on average (range: 80-110). The mean hospital stay was 4 days and pain was adequately controlled by administering 2 ml of Toradol twice daily. We believe that the advantages of the laparoscopic technique together with the efficacy of the radiofrequency instrument in liver surgery will lead to a more widespread use of this procedure and extension of its use to include the safe execution of both minor and major resections.

  14. Initial Experience in the Treatment of "Borderline Resectable" Pancreatic Adenocarcinoma.

    Science.gov (United States)

    Busquets, Juli; Fabregat, Juan; Verdaguer, Helena; Laquente, Berta; Pelaez, Núria; Secanella, Luis; Leiva, David; Serrano, Teresa; Cambray, María; Lopez-Urdiales, Rafael; Ramos, Emilio

    2017-10-01

    A borderline resectable group (APBR) has recently been defined in adenocarcinoma of the pancreas. The objective of the study is to evaluate the results in the surgical treatment after neoadjuvancy of the APBR. Between 2010 and 2014, we included patients with APBR in a neoadjuvant and surgery protocol, staged by multidetector computed tomography (MDCT). Treatment with chemotherapy was based on gemcitabine and oxaliplatin. Subsequently, MDCT was performed to rule out progression, and 5-FU infusion and concomitant radiotherapy were given. MDCT and resection were performed in absence of progression. A descriptive statistical study was performed, dividing the series into: surgery group (GR group) and progression group (PROG group). We indicated neoadjuvant treatment to 22 patients, 11 of them were operated, 9 pancreatoduodenectomies, and 2 distal pancreatectomies. Of the 11 patients, 7 required some type of vascular resection; 5 venous resections, one arterial and one both. No postoperative mortality was recorded, 7 (63%) had any complications, and 4 were reoperated. The median postoperative stay was 17 (7-75) days. The pathological study showed complete response (ypT0) in 27%, and free microscopic margins (R0) in 63%. At study clossure, all patients had died, with a median actuarial survival of 13 months (9,6-16,3). The median actuarial survival of the GR group was higher than the PROG group (25 vs. 9 months; p vascular resection in most cases. Copyright © 2017 AEC. Publicado por Elsevier España, S.L.U. All rights reserved.

  15. [Functional condition of pancreas after stomach resection according to Roux].

    Science.gov (United States)

    Kuzin, N M; Kanadashvili, O V; Maĭorova, E M

    2000-01-01

    Available are the results of surgical treatment of 90 patients with stenotic gastroduodenal ulcer in Burdenko Surgical Faculty Hospital of Sechenov Moscow Medical Academy between 1984 and 1985. 30 patients (study group) underwent stomach Roux-type resection. Truncal vagotomy with a stomach Bilroth-I resection was made in 20 control patients, after 20 control patients had a truncal vagotomy with pyloroplasty according to Heineke-Mikulicz, and 20 patients had selective proximal vagotomy with gastroduodenostomy by Joboulay (the third control group). Exocrine function of the pancreas was assessed by serum concentration of immunoreactive trypsin, endocrine function by fasting blood sugar, oral glucose tolerance and serum concentration of immunoreactive insulin. The authors came to the conclusion that exocrine function of the pancreas was equally damaged in patients with a Roux stomach resection, stem vagotomy with a stomach Bilroth-I resection and a stem vagotomy with pyloroplasty Heineke-Mikulicz. After selective proximal vagotomy a level of immunoreactive trypsin was normal. After a Roux stomach resection relative incompetence of basophil cells of the pancreas and long increase of insulin in the blood were observed but without influence on the glucose curve. The changes of glucose curve and level of immunoreactive insulin were similar in the control groups.

  16. Indirect Wafer Bonding and Epitaxial Transfer of GaSb-Based Materials

    Science.gov (United States)

    Grzesik, M.; Vangala, S. R.; Goodhue, W. D.

    2013-04-01

    Results from a study of indirect wafer bonding and epitaxial transfer of GaSb-based materials are presented. Benzocyclobutene (BCB) was used as a bonding agent to bond GaSb and epitaxial structures lattice matched to GaSb onto Si, GaAs, and sapphire carrier substrates. To better understand sources of stress during the bonding process, which can result in cracking and subsurface damage of the GaSb-based materials, BCB's hardness and reduced elastic modulus were measured at various stages during the curing process. Based on the results of curing experiments, a bonding and epitaxial transfer process for GaSb-based materials was then developed. Following bonding, using an experimentally determined low-stress cure cycle, GaSb substrates were removed from epitaxial layers of InAsSb using a combination of mechanical thinning and polishing followed by selective chemical etching using a hydrofluoric and chromic acid solution. Etch selectivity data are also presented where selectivity greater than 100:1 is achieved for GaSb:InAsSb.

  17. Theoretical analysis of improved efficiency of silicon-wafer solar cells with textured nanotriangular grating structure

    Science.gov (United States)

    Zhang, Yaoju; Zheng, Jun; Zhao, Xuesong; Ruan, Xiukai; Cui, Guihua; Zhu, Haiyong; Dai, Yuxing

    2018-03-01

    A practical model of crystalline silicon-wafer solar cells is proposed in order to enhance the light absorption and improve the conversion efficiency of silicon solar cells. In the model, the front surface of the silicon photovoltaic film is designed to be a textured-triangular-grating (TTG) structure, and the ITO contact film and the antireflection coating (ARC) of glass are coated on the TTG surface of silicon solar cells. The optical absorption spectrum of solar cells are simulated by applying the finite difference time domain method. Electrical parameters of the solar cells are calculated using two models with and without carrier loss. The effect of structure parameters on the performance of the TTG cell is discussed in detail. It is found that the thickness (tg) of the ARC, period (p) of grating, and base angle (θ) of triangle have a crucial influence on the conversion efficiency. The optimal structure of the TTG cell is designed. The TTG solar cell can produce higher efficiency in a wide range of solar incident angle and the average efficiency of the optimal TTG cell over 7:30-16:30 time of day is 8% higher than that of the optimal plane solar cell. In addition, the study shows that the bulk recombination of carriers has an influence on the conversion efficiency of the cell, the conversion efficiency of the actual solar cell with carrier recombination is reduced by 20.0% of the ideal cell without carrier recombination.

  18. Deposition uniformity, particle nucleation and the optimum conditions for CVD in multi-wafer furnaces

    Energy Technology Data Exchange (ETDEWEB)

    Griffiths, S.K.; Nilson, R.H.

    1996-06-01

    A second-order perturbation solution describing the radial transport of a reactive species and concurrent deposition on wafer surfaces is derived for use in optimizing CVD process conditions. The result is applicable to a variety of deposition reactions and accounts for both diffusive and advective transport, as well as both ordinary and Knudsen diffusion. Based on the first-order approximation, the deposition rate is maximized subject to a constraint on the radial uniformity of the deposition rate. For a fixed reactant mole fraction, the optimum pressure and optimum temperature are obtained using the method of Lagrange multipliers. This yields a weak one-sided maximum; deposition rates fall as pressures are reduced but remain nearly constant at all pressures above the optimum value. The deposition rate is also maximized subject to dual constraints on the uniformity and particle nucleation rate. In this case, the optimum pressure, optimum temperature and optimum reactant fraction are similarly obtained, and the resulting maximum deposition rate is well defined. These results are also applicable to CVI processes used in composites manufacturing.

  19. Corrugation Architecture Enabled Ultraflexible Wafer-Scale High-Efficiency Monocrystalline Silicon Solar Cell

    KAUST Repository

    Bahabry, Rabab R.

    2018-01-02

    Advanced classes of modern application require new generation of versatile solar cells showcasing extreme mechanical resilience, large-scale, low cost, and excellent power conversion efficiency. Conventional crystalline silicon-based solar cells offer one of the most highly efficient power sources, but a key challenge remains to attain mechanical resilience while preserving electrical performance. A complementary metal oxide semiconductor-based integration strategy where corrugation architecture enables ultraflexible and low-cost solar cell modules from bulk monocrystalline large-scale (127 × 127 cm) silicon solar wafers with a 17% power conversion efficiency. This periodic corrugated array benefits from an interchangeable solar cell segmentation scheme which preserves the active silicon thickness of 240 μm and achieves flexibility via interdigitated back contacts. These cells can reversibly withstand high mechanical stress and can be deformed to zigzag and bifacial modules. These corrugation silicon-based solar cells offer ultraflexibility with high stability over 1000 bending cycles including convex and concave bending to broaden the application spectrum. Finally, the smallest bending radius of curvature lower than 140 μm of the back contacts is shown that carries the solar cells segments.

  20. Wafer-Scale High-Throughput Ordered Growth of Vertically Aligned ZnO Nanowire Arrays

    KAUST Repository

    Wei, Yaguang

    2010-09-08

    This article presents an effective approach for patterned growth of vertically aligned ZnO nanowire (NW) arrays with high throughput and low cost at wafer scale without using cleanroom technology. Periodic hole patterns are generated using laser interference lithography on substrates coated with the photoresist SU-8. ZnO NWs are selectively grown through the holes via a low-temperature hydrothermal method without using a catalyst and with a superior control over orientation, location/density, and as-synthesized morphology. The development of textured ZnO seed layers for replacing single crystalline GaN and ZnO substrates extends the large-scale fabrication of vertically aligned ZnO NW arrays on substrates of other materials, such as polymers, Si, and glass. This combined approach demonstrates a novel method of manufacturing large-scale patterned one-dimensional nanostructures on various substrates for applications in energy harvesting, sensing, optoelectronics, and electronic devices. © 2010 American Chemical Society.

  1. Dehydration and dehydroxylation of C-S-H phases synthesized on silicon wafers

    Science.gov (United States)

    Giraudo, Nicolas; Bergdolt, Samuel; Laye, Fabrice; Krolla, Peter; Lahann, Joerg; Thissen, Peter

    2018-03-01

    In this work, the synthesis of specific ultrathin Calcium-Silicate-Hydrate (C-S-H) phases on silicon wafers and their transformation into C-S phases is achieved. Specific mineral phases are identified, and the synthesis is successful controlled. Samples are investigated by means of Fourier Transform Infrared (FTIR) spectroscopy and X-ray Diffraction (XRD) and the results are analyzed based on first-principles calculations. When C-S-H phases are transformed into C-S phases, only a few reflexes are detected on XRD, and the coherent scattering domains decrease with the increment of the temperature and time of exposure. This behavior is explained by the Ca/Si changes, which are identified by changes in the FTIR spectra. A thermodynamic analysis is performed with the help of first-principles calculations to underline the influence of the calcium-to-silicon (Ca/Si) ratio in the process of dehydroxylation. To increase the Ca/Si ratio water is partially substituted by methanol at the synthesis. This is observed in the FTIR spectra and is confirmed by lower temperatures of dehydroxylation. The catalytic nature of calcium towards the dehydroxylation is confirmed. The core of this work lies in the preparation of a model, which perfection makes possible to model reactivity, stability and mechanical properties using first-principles calculations, and is the starting point for the synthesis of many others.

  2. A Lateral Differential Resonant Pressure Microsensor Based on SOI-Glass Wafer-Level Vacuum Packaging

    Directory of Open Access Journals (Sweden)

    Bo Xie

    2015-09-01

    Full Text Available This paper presents the fabrication and characterization of a resonant pressure microsensor based on SOI-glass wafer-level vacuum packaging. The SOI-based pressure microsensor consists of a pressure-sensitive diaphragm at the handle layer and two lateral resonators (electrostatic excitation and capacitive detection on the device layer as a differential setup. The resonators were vacuum packaged with a glass cap using anodic bonding and the wire interconnection was realized using a mask-free electrochemical etching approach by selectively patterning an Au film on highly topographic surfaces. The fabricated resonant pressure microsensor with dual resonators was characterized in a systematic manner, producing a quality factor higher than 10,000 (~6 months, a sensitivity of about 166 Hz/kPa and a reduced nonlinear error of 0.033% F.S. Based on the differential output, the sensitivity was increased to two times and the temperature-caused frequency drift was decreased to 25%.

  3. Toward the synthesis of wafer-scale single-crystal graphene on copper foils.

    Science.gov (United States)

    Yan, Zheng; Lin, Jian; Peng, Zhiwei; Sun, Zhengzong; Zhu, Yu; Li, Lei; Xiang, Changsheng; Samuel, E Loïc; Kittrell, Carter; Tour, James M

    2012-10-23

    In this research, we constructed a controlled chamber pressure CVD (CP-CVD) system to manipulate graphene's domain sizes and shapes. Using this system, we synthesized large (~4.5 mm(2)) single-crystal hexagonal monolayer graphene domains on commercial polycrystalline Cu foils (99.8% purity), indicating its potential feasibility on a large scale at low cost. The as-synthesized graphene had a mobility of positive charge carriers of ~11,000 cm(2) V(-1) s(-1) on a SiO(2)/Si substrate at room temperature, suggesting its comparable quality to that of exfoliated graphene. The growth mechanism of Cu-based graphene was explored by studying the influence of varied growth parameters on graphene domain sizes. Cu pretreatments, electrochemical polishing, and high-pressure annealing are shown to be critical for suppressing graphene nucleation site density. A pressure of 108 Torr was the optimal chamber pressure for the synthesis of large single-crystal monolayer graphene. The synthesis of one graphene seed was achieved on centimeter-sized Cu foils by optimizing the flow rate ratio of H(2)/CH(4). This work should provide clear guidelines for the large-scale synthesis of wafer-scale single-crystal graphene, which is essential for the optimized graphene device fabrication.

  4. Wafer-scale design of lightweight and transparent electronics that wraps around hairs

    Science.gov (United States)

    Salvatore, Giovanni A.; Münzenrieder, Niko; Kinkeldei, Thomas; Petti, Luisa; Zysset, Christoph; Strebel, Ivo; Büthe, Lars; Tröster, Gerhard

    2014-01-01

    Electronics on very thin substrates have shown remarkable bendability, conformability and lightness, which are important attributes for biological tissues sensing, wearable or implantable devices. Here we propose a wafer-scale process scheme to realize ultra flexible, lightweight and transparent electronics on top of a 1-μm thick parylene film that is released from the carrier substrate after the dissolution in water of a polyvinyl- alcohol layer. The thin substrate ensures extreme flexibility, which is demonstrated by transistors that continue to work when wrapped around human hairs. In parallel, the use of amorphous oxide semiconductor and high-K dielectric enables the realization of analogue amplifiers operating at 12 V and above 1 MHz. Electronics can be transferred on any object, surface and on biological tissues like human skin and plant leaves. We foresee a potential application as smart contact lenses, covered with light, transparent and flexible devices, which could serve to monitor intraocular pressure for glaucoma disease.

  5. Methodology For Reduction Of Sampling On The Visual Inspection Of Developed And Etched Wafers

    Science.gov (United States)

    van de Ven, Jamie S.; Khorasani, Fred

    1989-07-01

    There is a lot of inspection in the manufacturing of semiconductor devices. Generally, the more important a manufacturing step, the higher is the level of inspection. In some cases 100% of the wafers are inspected after certain steps. Inspection is a non-value added and expensive activity. It requires an army of "inspectors," often times expensive equipment and becomes a "bottle neck" when the level of inspection is high. Although inspection helps identify quality problems, it hurts productivity. The new management, quality and productivity philosophies recommend against over inspection. [Point #3 in Dr. Deming's 14 Points for Management (1)] 100% inspection is quite unnecessary . Often the nature of a process allows us to reduce inspection drastically and still maintain a high level of confidence in quality. In section 2, we discuss such situations and show that some elementary probability theory allows us to determine sample sizes and measure the chances of catching a bad "lot" and accepting a good lot. In section 3, we provide an example and application of the theory, and make a few comments on money and time saved because of this work. Finally, in section 4, we draw some conclusions about the new quality and productivity philosophies and how applied statisticians and engineers should study every situation individually and avoid blindly using methods and tables given in books.

  6. Tailoring the graphene/silicon carbide interface for monolithic wafer-scale electronics.

    Science.gov (United States)

    Hertel, S; Waldmann, D; Jobst, J; Albert, A; Albrecht, M; Reshanov, S; Schöner, A; Krieger, M; Weber, H B

    2012-07-17

    Graphene is an outstanding electronic material, predicted to have a role in post-silicon electronics. However, owing to the absence of an electronic bandgap, graphene switching devices with high on/off ratio are still lacking. Here in the search for a comprehensive concept for wafer-scale graphene electronics, we present a monolithic transistor that uses the entire material system epitaxial graphene on silicon carbide (0001). This system consists of the graphene layer with its vanishing energy gap, the underlying semiconductor and their common interface. The graphene/semiconductor interfaces are tailor-made for ohmic as well as for Schottky contacts side-by-side on the same chip. We demonstrate normally on and normally off operation of a single transistor with on/off ratios exceeding 10(4) and no damping at megahertz frequencies. In its simplest realization, the fabrication process requires only one lithography step to build transistors, diodes, resistors and eventually integrated circuits without the need of metallic interconnects.

  7. Wafer-scale production of vertical SnS multilayers for high-performing photoelectric devices.

    Science.gov (United States)

    Patel, Malkeshkumar; Kim, Hong-Sik; Kim, Joondong

    2017-10-26

    This study achieved wafer-scale, high quality tin monosulfide (SnS) layers. By using a solid-state reaction, the vertically aligned SnS layers spontaneously grew with sulphur reduction from the sputtered SnS 2 particles without any post processes. The quality of the SnS vertical layers was observed by high resolution transmission electron microscopy, which confirmed an interlayer space of 0.56 nm for a perfect match to the theoretical value. The phase purity of SnS was confirmed by Raman spectroscopy. The intrinsic energy band gap value (1.6 eV) of SnS is attractive for photoelectric devices. To form a heterojunction, the vertical SnS layers were grown on a n-type Si substrate. Due to the nanoscale size and vertical standing features of the SnS layers, a significantly low reflection (cell, the device provides a higher open circuit voltage (>300 mV). For photodetection, the response speed is faster than 15 μs for near infrared wavelength photons, which is a 1000 times improvement over the horizontally shaped device. The vertically standing SnS layers show high photoreactive performance, which confirms that the functional design of 2D materials is an effective route to achieve enhanced photoelectric devices, such as photodetectors and solar cells.

  8. Characterization of a vertically movable gate field effect transistor using a silicon-on-insulator wafer

    International Nuclear Information System (INIS)

    Song, In-Hyouk; Forfang, William B D; Cole, Bryan; Hee You, Byoung

    2014-01-01

    The vertically movable gate field effect transistor (VMGFET) is a FET-based sensing element, whose gate moves in a vertical direction over the channel. A VMGFET gate covers the region between source and drain. A 1 μm thick air layer separates the gate and the substrate of the VMGFET. A novel fabrication process to form a VMGFET using a silicon-on-insulator (SOI) wafer provides minimal internal stress of the gate structure. The enhancement-type n-channel VMGFET is fabricated with the threshold voltage of 2.32 V in steady state. A non-inverting amplifier is designed and integrated on a printable circuit board (PCB) to characterize device sensitivity and mechanical properties. The VMGFET is mechanically coupled to a speaker membrane to apply mechanical vibration. The oscillated drain current of FET are monitored and sampled with NI LabVIEW. The frequency of the output signal correlates with that of the input stimulus. The resonance frequency of the fabricated VMGFET is measured to be 1.11 kHz. The device sensitivity linearly increases by 0.106 mV/g Hz in the range of 150 Hz and 1 kHz. (paper)

  9. The development of the wafer cost and availability for the photovoltaic industry

    International Nuclear Information System (INIS)

    Herzer, H.

    1991-01-01

    The photovoltaic (PV) industry is a young industry which has not yet matured to handle its business in a profitable way. One of the main reasons is the conflict between operating technologies, real costs, and diversified applications under loss-generating market conditions and the big visions to make photovoltaics become a renewable clean energy source for the future. A driving force always has been the projection of low-cost metallurgical sand reduction combined with ribbon/sheet approaches if c-Si is concerned, and the advent of a-Si and thin film technologies if alternatives and c-Si replacing materials are concerned. Today, we recognize a concentration towards c-Si as the basic material for power PV modules and systems. With regard to the scientific/technological state of the art, even here, a wide range of methods are presently investigated. The potential in terms of efficiency and cost-advantages/disadvantages will be commented. Looking at the industrial status of large-scale production commercial and economical aspects are dominating, bringing everything to the classical production of monocrystalline and multicrystalline wafers, both in connection with ID or multi-wire cutting. 5 figs., 4 tabs., 12 refs

  10. 14C autoradiography with a novel wafer scale CMOS Active Pixel Sensor

    International Nuclear Information System (INIS)

    Esposito, M; Wells, K; Anaxagoras, T; Allinson, N M; Larner, J

    2013-01-01

    14 C autoradiography is a well established technique for structural and metabolic analysis of cells and tissues. The most common detection medium for this application is film emulsion, which offers unbeatable spatial resolution due to its fine granularity but at the same time has some limiting drawbacks such as poor linearity and rapid saturation. In recent years several digital detectors have been developed, following the technological transition from analog to digital-based detection systems in the medical and biological field. Even so such digital systems have been greatly limited by the size of their active area (a few square centimeters), which have made them unsuitable for routine use in many biological applications where sample areas are typically ∼ 10–100 cm 2 . The Multidimensional Integrated Intelligent Imaging (MI3-Plus) consortium has recently developed a new large area CMOS Active Pixel Sensor (12.8 cm × 13.1 cm). This detector, based on the use of two different pixel resolutions, is capable of providing simultaneously low noise and high dynamic range on a wafer scale. In this paper we will demonstrate the suitability of this detector for routine beta autoradiography in a comparative approach with widely used film emulsion.

  11. Best depth of focus on 22-nm logic wafers with less shot count

    Science.gov (United States)

    Fujimura, Aki; Kim, David; Komagata, Tadashi; Nakagawa, Yasutoshi; Tolani, Vikram; Cecil, Tom

    2010-05-01

    The contact layer for the 22 nm logic node faces many technological hurdles. Even using techniques such as multiple-exposure patterning and 193 nm immersion, it will be difficult to achieve the depth of focus and CD uniformity required for 22 nm production. Such difficulties can be mitigated by recent advances in Inverse Lithography Technology (ILT). For example, circular main features combined with complex curvilinear assist features can provide superior CD uniformity with the required depth of focus, particularly for isolated contacts. However, such a solution can lead to long mask write times, because the curvilinear shapes necessitate a higher shot count induced by inefficient data fracturing, even without considering the circular main features. The current approach is to Manhattanize the curvilinear features resulting in a nearly equivalent image quality on the wafer; but a further reduction in mask write times could help lower costs. This paper describes a novel mask-writing method that uses a production e-beam mask writer to write main features as circles, with curvilinear assist features, while reducing shot count compared to traditional Manhattanized masks. As a result the new method makes manufacturing of ideal ILT-type masks feasible from a technical as well as from an economic standpoint. Resist-exposed SEM images are presented that validate the new method.

  12. Atomic layer lithography of wafer-scale nanogap arrays for extreme confinement of electromagnetic waves.

    Science.gov (United States)

    Chen, Xiaoshu; Park, Hyeong-Ryeol; Pelton, Matthew; Piao, Xianji; Lindquist, Nathan C; Im, Hyungsoon; Kim, Yun Jung; Ahn, Jae Sung; Ahn, Kwang Jun; Park, Namkyoo; Kim, Dai-Sik; Oh, Sang-Hyun

    2013-01-01

    Squeezing light through nanometre-wide gaps in metals can lead to extreme field enhancements, nonlocal electromagnetic effects and light-induced electron tunnelling. This intriguing regime, however, has not been readily accessible to experimentalists because of the lack of reliable technology to fabricate uniform nanogaps with atomic-scale resolution and high throughput. Here we introduce a new patterning technology based on atomic layer deposition and simple adhesive-tape-based planarization. Using this method, we create vertically oriented gaps in opaque metal films along the entire contour of a millimetre-sized pattern, with gap widths as narrow as 9.9 Å, and pack 150,000 such devices on a 4-inch wafer. Electromagnetic waves pass exclusively through the nanogaps, enabling background-free transmission measurements. We observe resonant transmission of near-infrared waves through 1.1-nm-wide gaps (λ/1,295) and measure an effective refractive index of 17.8. We also observe resonant transmission of millimetre waves through 1.1-nm-wide gaps (λ/4,000,000) and infer an unprecedented field enhancement factor of 25,000.

  13. Imaging ATUM ultrathin section libraries with WaferMapper: A multi-scale approach to EM reconstruction of neural circuits

    Directory of Open Access Journals (Sweden)

    Kenneth Jeffrey Hayworth

    2014-06-01

    Full Text Available The automated tape-collecting ultramicrotome (ATUM makes it possible to collect large numbers of ultrathin sections quickly—the equivalent of a petabyte of high resolution images each day. However, even high throughput image acquisition strategies generate images far more slowly (at present ~1 terabyte per day. We therefore developed WaferMapper, a software package that takes a multi-resolution approach to mapping and imaging select regions within a library of ultrathin sections. This automated method selects and directs imaging of corresponding regions within each section of an ultrathin section library that may contain many thousands of sections. Using WaferMapper, it is possible to map all the sections at low resolution and target multiple points of interest for high resolution imaging based on anatomical landmarks. The program can also be used to expand previously imaged regions, acquire data under different imaging conditions, or re-image after additional tissue treatments.

  14. Imaging ATUM ultrathin section libraries with WaferMapper: a multi-scale approach to EM reconstruction of neural circuits.

    Science.gov (United States)

    Hayworth, Kenneth J; Morgan, Josh L; Schalek, Richard; Berger, Daniel R; Hildebrand, David G C; Lichtman, Jeff W

    2014-01-01

    The automated tape-collecting ultramicrotome (ATUM) makes it possible to collect large numbers of ultrathin sections quickly-the equivalent of a petabyte of high resolution images each day. However, even high throughput image acquisition strategies generate images far more slowly (at present ~1 terabyte per day). We therefore developed WaferMapper, a software package that takes a multi-resolution approach to mapping and imaging select regions within a library of ultrathin sections. This automated method selects and directs imaging of corresponding regions within each section of an ultrathin section library (UTSL) that may contain many thousands of sections. Using WaferMapper, it is possible to map thousands of tissue sections at low resolution and target multiple points of interest for high resolution imaging based on anatomical landmarks. The program can also be used to expand previously imaged regions, acquire data under different imaging conditions, or re-image after additional tissue treatments.

  15. A wafer-scale backplane-assisted resonating nanoantenna array SERS device created by tunable thermal dewetting nanofabrication

    Science.gov (United States)

    Chang, Te-Wei; Ranjan Gartia, Manas; Seo, Sujin; Hsiao, Austin; Logan Liu, Gang

    2014-04-01

    A tunable lithography-less nanofabrication process using a metal thin-film thermal dewetting technique has been developed to fabricate wafer-scale and uniform plasmonic substrates at low cost for optimal performance in surface enhanced Raman scattering (SERS) applications. The relationship between the tunable parameters of this process and the corresponding optical and plasmonic characteristic is investigated both experimentally and theoretically to understand the deterministic design of an optimal SERS device with a three-dimensional plasmonic nanoantenna structure. The enhancement of SERS using various nanoplasmonic particle sizes, structure lengths, lateral hot spot spacings and resonating effects are examined and demonstrated. We achieve a uniform optimal enhancement factor of 1.38 × 108 on a 4 in wafer-scale SERS substrate with a backplane-assisted resonating nanoantenna array design. Sensitive environmental nitrate sensing, vitamin detection and oligonucleotide identification are demonstrated on the high-performance SERS device.

  16. High efficiency heterojunction solar cells on n-type kerfless mono crystalline silicon wafers by epitaxial growth

    Science.gov (United States)

    Kobayashi, Eiji; Watabe, Yoshimi; Hao, Ruiying; Ravi, T. S.

    2015-06-01

    We present a heterojunction (HJ) solar cell on n-type epitaxially grown kerfless crystalline-silicon (c-Si) with a conversion efficiency of 22.5%. The total cell area is 243.4 cm2. The cell has a short-circuit current density of 38.6 mA/cm2, an open-circuit voltage of 735 mV, and a fill factor of 0.791. The key advantages and technological tasks of epitaxial wafers for HJ solar cells are discussed, in comparison with conventional n-type Czockralski c-Si wafers. The combination of HJ and kerfless technology can lead to high conversion efficiency with a potential at low cost.

  17. Growth of carbon nanotubes on Si/SiO2 wafer etched by hydrofluoric acid under different etching durations

    International Nuclear Information System (INIS)

    Tan, Lling-Lling; Chai, Siang-Piao; Mohamed, Abdul Rahman

    2012-01-01

    The preparation of SiO 2 nanoparticles for the metal-free catalyst growth of carbon nanotubes (CNTs) was investigated. SiO 2 nanoparticles were generated by etching Si/SiO 2 wafers with 48-50% hydrofluoric acid. Etching duration was varied to study its effects on the generation of the SiO 2 nanoparticles. Atomic force microscopy characterization showed that etching at 1 min was the most effective considering the significant numbers of SiO 2 nanoparticles obtained under this condition. The wafer etched at 1 min after chemical vapor deposition at 900 °C for 1 h demonstrated a low I D /I G from Raman analysis which establishes that CNTs with highly ordered graphitic structures were grown. Raman analysis also showed a strong radial breathing mode peak in the low-frequency range for the substrate following the 1 min etching process after the reaction.

  18. Increasing reticle inspection efficiency and reducing wafer printchecks at 14nm using automated defect classification and simulation

    Science.gov (United States)

    Paracha, Shazad; Goodman, Eliot; Eynon, Benjamin G.; Noyes, Ben F.; Ha, Steven; Kim, Jong-Min; Lee, Dong-Seok; Lee, Dong-Heok; Cho, Sang-Soo; Ham, Young M.; Vacca, Anthony D.; Fiekowsky, Peter J.; Fiekowsky, Daniel I.

    2014-10-01

    IC fabs inspect critical masks on a regular basis to ensure high wafer yields. These requalification inspections are costly for many reasons including the capital equipment, system maintenance, and labor costs. In addition, masks typically remain in the "requal" phase for extended, non-productive periods of time. The overall "requal" cycle time in which reticles remain non-productive is challenging to control. Shipping schedules can slip when wafer lots are put on hold until the master critical layer reticle is returned to production. Unfortunately, substituting backup critical layer reticles can significantly reduce an otherwise tightly controlled process window adversely affecting wafer yields. One major requal cycle time component is the disposition process of mask inspections containing hundreds of defects. Not only is precious non-productive time extended by reviewing hundreds of potentially yield-limiting detections, each additional classification increases the risk of manual review techniques accidentally passing real yield limiting defects. Even assuming all defects of interest are flagged by operators, how can any person's judgment be confident regarding lithographic impact of such defects? The time reticles spend away from scanners combined with potential yield loss due to lithographic uncertainty presents significant cycle time loss and increased production costs An automatic defect analysis system (ADAS), which has been in fab production for numerous years, has been improved to handle the new challenges of 14nm node automate reticle defect classification by simulating each defect's printability under the intended illumination conditions. In this study, we have created programmed defects on a production 14nm node critical-layer reticle. These defects have been analyzed with lithographic simulation software and compared to the results of both AIMS optical simulation and to actual wafer prints.

  19. An experimental and theoretical study of pendellösung fringes in synchrotron section topographs of silicon wafers.

    Science.gov (United States)

    Partanen, J; Tuomi, T

    1990-01-01

    X-ray section topographs of nearly perfect Czochralski-grown wafers were made with synchrotron radiation having a continuous spectrum. An intensity curve measured from the x-ray film is compared to the calculated curve obtained using the dynamical theory of x-ray diffraction. A computer simulation of the topograph is also presented. A good agreement between theory and experiment is found except in the middle part of the topograph.

  20. High performance few-layer MoS2 transistor arrays with wafer level homogeneity integrated by atomic layer deposition

    Science.gov (United States)

    Zhang, Tianbao; Wang, Yang; Xu, Jing; Chen, Lin; Zhu, Hao; Sun, Qingqing; Ding, Shijin; Zhang, David Wei

    2018-01-01

    Wafer-level integration of 2D transition metal disulfide is the key factor for future large-scale integration of the continuously scaling-down devices, and has attracted great attention in recent years. Compared with other ultra-thin film growth methods, atomic layer deposition (ALD) has the advantages of excellent step coverage, uniformity and thickness controllability. In this work, we synthesized large-scale and thickness-controllable MoS2 films on sapphire substrate by ALD at 150 °C with molybdenum hexcarbonyl and hexamethyldisilathiane (HMDST) as precursors followed by high-temperature annealing in sulfur atmosphere. HMDST is introduced for the first time to enable a toxic-free process without hazardous sulfur precursors such as H2S and CH3SSCH3. The synthesized MoS2 retains the inherent benefits from the ALD process, including thickness controllability, reproducibility, wafer-level thickness uniformity, and high conformity. Finally, field-effect transistor (FET) arrays were fabricated based on the large-area ALD MoS2 films. The top-gate FETs exhibited excellent electrical performance such as high on/off current ratio over 103 and peak room-temperature mobility up to 11.56 cm2 V‑1 s‑1. This work opens up an attractive approach to realize the application of high-quality 2D materials with wafer scale homogeneity.